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11/05/15 New testing results from the Sigma 20mm 1.4 Art lens at lenstip.com

Posted on November 6, 2015 //
Sigma 20mm F 1.4 Art lens

Sigma 20mm F 1.4 Art Lens

As of this afternoon, the first full review of the new Sigma 20mm 1.4 has been published over on www.lenstip.com  You can read the full review here: Lenstip 20mm 1.4 Sigma review

From a quick read I have determined the following:

  1. The resolution of this lens can be expected to be superior to pretty much all other 20mm fast lenses out there, including the recent Nikon 20mm 1.8.  It seems that the center resolution even at F1.4 is excellent and by F3.5 to F4.0 the corners are very sharp also.
  2. There might be some issues with Chromatic aberrations, but hopefully the LR lens profile when available will correct for this. The build quality is as expected, excellent as with all the Sigma Art glass
  3. Coma, sadly it seems that this lens falls a bit short with coma corrections.  Per the testing at Lenstip, there are pretty harsh coma issues from F1.4 till F 2.0.  From their examples, it appears to me that these coma issues are as bad as with the 24mm 1.4 Sigma Art lens.  However the example shown at F2.0 looks pretty good to me as there     are butterfly wings showing, but nothing like what the Nikon 20mm F 1.8 shows at F 2.0 or even F 2.5.  I had hoped that this new lens, which Sigma states “is specifically designed to remove coma” would fare a bit better.  In daylight work, the coma aberrations may not show up, but anyone wanting to use this lens at night for astro-photography will be a bit disappointed as the quest has always been to get a wide that will work at F 1.4 without coma.
  4. Build quality appears to be as with all the Art line of lenses, excellent.

 

Sigma top view of 20mm F 1.4 Art lens

Sigma top view of 20mm F 1.4 Art lens

My main need for a fast wide, is night photography, where the difference between F 2.8 and F 1.4 is huge and can allow for a vastly different quality image as you can shoot short exposures of the Milky Way and other starscapes without having to be at a grossly high iso setting like ISO 12800.  There was no mention of the bokeh wide open, and again I am hoping to see something better than Sigma was able to provide for the 24mm F 1.4 which to my eyes has a very disruptive bokeh on landscapes, not as much on macro work.

The new Sigma Art 20mm 1.4 already has one strike against it with the fact that it has a fixed hood, and curved outer element which eliminates the ability to use standard filters.  Hopefully Lee or another company will come out with an adapter for this lens to use the SW-150 filter setup or something similar.

I have one of the new 20mm 1.4’s on order, hopefully it will ship sometime mid November, but I am not expecting it until December.

Sigma 20mm F1.4 Art Lens dual Views

Sigma 20mm F1.4 Art Lens dual Views

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03/15/13 Interesting Feedback on the new Phase One IQ2X Digital Backs

Posted on March 15, 2013 //
Phase One IQ260 and IQ280 Digital Backs

Phase One IQ260 and IQ280 Digital Backs

 

 

After following some of the more prominent web forums it has been interesting to see how the feedback on the new Phase One IQ2X backs has filtered down.  I have watched the frenzy from the first day back on the 4th of March drop to more of an even pace.  The reactions have been mixed to say the least.  For sure the greatest single comment has been why Phase One did not implement CMOS and come out with a more useable form of live view.  This is true across the entire lineup.  But as you filter down to the 260, 280 and Achromatic  back, opinions seem to vary.

IQ260:

  1. The biggest interest  has been over long exposures again coming to a current MFD digital back.  I have already written a lot about my thoughts on this, and you can read them in this post.   Net it seems that many people are still fascinated by the ability to have a MFD digital back that will reach 1 hour in a continuous exposure.  I am not, at least for my current photographic needs.  I am still much more interested in how much improvement is at base iso 50 if any.
  2. Can the noise coefficient at base iso 50 be improved over the current IQ160.  I feel this a huge issue.  Nikon has proven it can easily get 3 stops of DR at the base iso of 100.  I don’t know of any other current Digital camera that can do this.  It’s really amazing as just how much you can push the shadows and still get a useable image.  Many seem to feel that the IQ180 can do this also.  I strongly disagree as even at it’s base iso of 35, I found more noise in the shadows of image when pushed, considerably more than the IQ160 at iso50. The IQ260 is a new chip and I am hoping all new controller cards, thus hopefully the DR at the base iso can be improved maybe as much as 1 to 1 1/2 stops.  
  3. What will the IQ260 allow for it’s longest exposure at base iso of 50.  Currently the IQ160 is rated to about 30 seconds.  I have taken mine to 45 seconds at iso 50, but that is a real push.  I am hoping that photographers will be able to get up to 2 minutes at iso 50 before things get out of control
  4. I am surprised that more photographers are not concerned about the hit that their current IQ160’s just took on residual value.  NET, there is not point in the purchase of a new IQ160 and used ones will start to fall in value as soon as the IQ260’s start to ship.  I feel this will start to max out in about 8 months from the first ship in June.  There will be folks out using a P65+ that may want to upgrade to the IQ160 instead of the IQ260, but I feel that is a big waste of money.  The chips in the P65+ and IQ160 are the same, so the only gain you get is the new IQ interface.  It’s pretty hard to justify the upgrade cost from the P65+ to the IQ160 just for this interface.  On the other hand it does make very good sense to upgrade from a P65+ to a IQ260.  You have the IQ interface and an all new chip set.
  5. What will the IQ260 do the value of the P45+?  More than likely it will increase in value as the hurdle to get to a IQ260 is much higher in most cases than a use P45+.  But used P45+’s carry some possible baggage. 
  6. There has been a lot of good talk about the WiFi abilities  of the IQ260.  My opinion on that is still out.  Personally, I am not going to try to communicate to a ipad or Macbook air in the field.  Just adds more to carry.   You can’t begin to transfer a full raw file and if you could to a ipad? What good is that.  To a Macbook air maybe you work on the file but unless you own the most current generation of Macbook air, you can only get to 4GB of ram and that is nowhere enough to process out a IQ back file from any camera.   Does wifi for preview make any sense maybe.  You will have a larger screen with a ipad or ipad mini, but it’s still a step away from the camera to review the file and then come back to delete it.  Studio shooters have a different set of needs.  I can assure you that in the outdoors on the normal day, the screen of a ipad or Macbook Air will be just as hard to see as the screen on the IQ260, basically next to impossible.  I have not read about any capabilities to control a DF camera via wifi.  That might be interesting.

IQ280:

  1. Basically there seems to be no interest in the IQ280 from current IQ180 users.  I can understand this as it’s the same chip tweaked to get 1/2 a stop of DR.   IThis might help the IQ280 in shadows with noise.  Phase One did not offer a very aggressive deal to IQ180 owners to make the move.   Also their current IQ180’s won’t take as near a residual hit since the chipset is same, just with newer features like wifi.  That is a stretch for the price of the upgrade.
  2. New buyers considering a IQ180, more than likely will just move over to the IQ280. 
  3. There has been no mention of upgrades to the Leaf Credo lineup of backs so for now it seem that all the new features will only come with the IQ2X backs.
  4. Since the IQ280 has the same 80-MP chip set it will have the same issues with certain tech camera lenses, namely the Schneider wides of 28mm, 35mm and 43mm. 
  5. Many also seem to feel that Phase One will be coming soon with a CMOS 80mp solution.  They might be but I not found any reference to any chip maker and a 80mp CMOS solution in the MFD size.  Not to say one it not out there and Phase is coming out with it.   However I still feel that if and when this happens it will 36mp to 45mp first and then the next generation will move to the 60MP and up sizes.

Achromatic Back

There has been a lot of talk about this back but in reality at the price point you have to be pretty much a dedicated black and white shooter to justify one.  I realize that it will have some amazing resolution at 60mp since there will be no color interpolation being done.  But the software conversions that are out there now such as Silver Efex pro or just the conversions that can be done in Capture One or Lightroom, make this a very expensive back indeed.

 

For now I am moving forward with plans to purchase a upgrade to the IQ260.  I have yet to really see any files that represent my style of photography.  If I don’t see a difference in the shadows of a base iso 50 file when pushed 2 to 2.5 stops I will cancel the upgrade.  I already know that I won’t need the IQ260 for longer exposures like 30 minutes or longer.  I also feel that none of the current Phase digital backs are good candidates for night photography utilizing stacking.  Stacking is by far the best way to maximize both the night sky and the foreground in a night landscape image.  Hopefully I will be able to shoot the IQ260 in mid April in Dallas with Digital Transitions.  Odds are it will be only a indoor shoot which is a total waste of time for me, but I may get lucky and they will allow for some outdoor shots.  Digital Transitions has a IQ260 in New York and they have been adding new images to their blog daily.

 

 

 

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03/13/13 30 minute or Longer Exposures and IQ260, Do they make sense

Posted on March 14, 2013 //

Since Phase One announced the new IQ260, the majority of the talk has been about the use of this new back with long exposures, exposures up to 1 hour in length.  One aspect is the use of this back in night photography, where the photographer is working to capture the movement of the earth against the stars in the night sky which creates star trails.  If you dial down in to the features of the IQ260, you will find that it is going to operate pretty much the same way the older P45+ did, expect it will be using a higher base iso of 140.  If you have done a lot of night photography (I have logged hundreds of hours maybe over a thousand in the past 4 years) you may want to consider some of the points I have brought up.

Night Skies over Roark Bluff on the Buffalo River in Arkansas

45 minute single exposure taken with a Phase One P45+

I have been fascinated by the idea of longer exposures since I started in photography over 30 years ago.  More recently my  interests moved to  long exposures of the night sky of 1 hour or longer. Needless to say, when Phase One first announced the P45+ back in late 2007 I was quick to get on board, as it was really the 1st true digital camera that could handle this.  Yes the first.  Consider what was out there on the market in the Canon DSLR lineup. The Canon 1ds MKIII was announced but still not shipping the Canon 1ds MKII could barely handle iso 800 and no way could it do a exposure close to 1 hour long. The Canon 5D MKI was on the market and amazing folks with it’s clean files but it still had trouble when moving into longer exposures than 10 minutes.  Nikon I believe still did not have the D700 on the market and none of their pro bodies marketed at the time  would get a clean  1 hour exposure.  So when Phase One announced 1 hour, on a CCD it was big news.  Of course it didn’t happen until much later, more like mid 2008 and it took Phase One a few upgrades to get there, but they did it.  More importantly, it worked, and worked quite well within some limitations.

  1. Iso 50 only for exposures 30 minutes or longer
  2. Outdoor ambient temperature max 69 degree F for 1 hour exposures
  3. Lower humidity the better
  4. Mandatory dark frame after each long exposure (Long Exposure Noise Reduction)
  5. No more than 2 long exposures of 40 minutes or longer per battery

I was able to work within these limitations, some of which I found out about as I went out and started shooting, mainly the outdoor temperature limitations.  Trust me, if you try it past 69 degrees you will get a ruined image.  However during this time the DSLR world caught up with Phase One and quickly passed them with newer CMOS solutions.  All of a sudden, Canon had the 5D MKII and it truly was a wonder camera.  The 5D MKII set down some baselines in both noise and exposure length, standards that are still being used today 5 years later.

Canon allowed you to have a 22mp sensor in CMOS that would take a exposure as long as you wanted, (within reason is about 4 hours).  You still had to take a dark frame after this shot, but that is pretty much the norm on any exposure this long.  If you need to go longer, it’s back to film.  Canon did however allow you to control the LEN (Long Exposure Noise Reduction).  So for shorter exposures, you could elect to turn it off.  I believe Canon was the first camera company to allow this, quickly followed by Nikon and Sony.  One of the main reasons this is important is that if you are a night photographer, the best way to capture the night sky in by stacking.  Stacking allows you to work with ambient moonlight.  This moonlight will both illuminate the foreground of your shot so you have a true landscape image and it gives the night sky a wonderful blue hue.  If you leave the camera open for just one long exposure, your night sky will be overexposed and thus only the brightest stars will show.  So I quickly learned that stacking was the way to go for my work.

I was enamored enough by Phase One and the P45+ to continue to work with it in my night photography.  However with stacking the Phase One solution begins to have some pretty harsh limitations.

  1. the mandatory dark frame creates gaps in the star trails
  2. no interval timer for the Mamiya/Phase one camera body
  3. lack of corner sharpness with most Mamiya/Phase One wide angle lenses
  4. quick fall off of image quality with increases in iso past 50

Let me examine each of these in more detail.

1.  Mandatory dark frame creates gaps in the star trails.  This is a big problem.  Stacking requires that you figure out the best combination of iso, aperture and exposure for the specific night.  This will always be different due the amount of moonlight available.  For example a on a recent night shoot I found the combination to be iso 400, F4.5, for 2 minutes.  The best aperture for star work would be fully wide open, however no lens I have works that well wide open, so I tend to shoot at F3.2 to F5.  If you go any higher you will start to miss the faint stars.  This an easy solution for any current Nikon or Canon DSLR body, however with the P45+ or IQ260 you are going to be locked into a mandatory dark frame after each shot.  So here I would have 2 minute gap between each exposure.  This will ruin the flow of the star trails.  However there are 3rd party software applications out there that will fix this. I have found  they don’t play well with medium format lenses and I was never able to figure out the correct FOV to get the software to work.   This issue quickly made me move back to a single continuous exposure with a Phase One back.

2.  No interval timer for the Mamiya/Phase One camera body.  The only remote for the Phase One DF body is a basic single fire remote.  You can lock it for a longer exposure, but you can’t set it to take intervals which is necessary for stacking.  Thus you have to either hold it down for 2 minutes, and release, or lock it and watch a timer for 2 minutes.  Trust me over time say 40 minutes, you will make mistakes and end up not getting a even exposure process. This is an issue around the medium format camera body, so no matter which digital back you use, P45+ or IQ260, you will have to manually control it.

3. Lack of corner sharpness with most Mamiya/Phase One wide angle lenses.  This is just a given and the main reason I moved over to a tech camera for medium format as most of my photography requires wide angle lenses.   With night photography you are after the sky as your main subject which main you need to lead with a wide angle lens. You need to use as large an aperture opening as you can within reason.  The Mamiya 35mm F3.5 is really soft at F3.5 and does not really begin to get sharp until F8.  At F8, you will miss most of the stars in the sky.  The Mamiya 45mm F2.8 has the same problems  I briefly tried the Mamiya 28mm F4.5 but it really has trouble wide open and mine would not get sharp on the corners until F11.  With DSLRs you have a lot more lenses to try and odds are you will find one that will get the job done.  For example the Samyang 14mm F2.8 has really shown that it can get the job done from F4 on up and it costs less than $400.00.

4.  Quick fall off of image quality past the base iso of 50.  Phase One pretty much designed the longer exposures on the P45+ around iso 50.  You could try it longer at iso 100 and iso 200, but by 200 you were picking up  dark spots on the sensor.  These are not really noise but some form of digital reticulation.  I will get these same spots on Canon imagers when they start to get hot or are working in really hot evening temperatures past 85 degrees F.   These dark spots will ruin your image as nothing will really remove them.  You also will start to pick up enough noise that the quality of the image is compromised.  The iso 50 limitation was the other main reason I moved back to DSLR 35mm cameras since many times I will need to stack at iso 400 and sometimes as high as iso 800 which is beyond the realm of the P45+.  The newly announced IQ260 may handle this a bit better since it moves up to iso 140 when you start to take a longer exposure.

My point of all of this, is when you move away from the marketing hype and start working with long exposures of the night sky, you will start to realize that you are going to limit yourself to very specific shooting situations with a medium format digital back.  I am still hoping that with the new CCD sensor in the IQ260, photographers may be able to gain as much as 1.5 to 2 stops on range in the lower iso ranges of 50 t0 200.  The fact that the IQ260 is showing very good results up to 8 minutes in current testing is promising.  However I am much more interested in see exposures of 1 minute or less at iso 50 to determine if the shadow noise is less than what is contained in the current IQ160.

 

 

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10/09/12 Further information on the D600 and MC-DC2 & MC-36

Posted on October 9, 2012 //
MC-30 to MC-DC2 converter

MC-30 to MC-DC2 converter

I have done a bit more research on the D600 and the remote timer issues.  Both the D800 and D600 come with a built in set of timers called:

  • Time lapse photography
  • Interval timer

One of my main goals was to use the D600 in my night photography pursuits.  Over a year ago, I stopped taking just single long exposures on the blub setting, and started to shoot stacks.  An example of a stack, is to shoot over a period of 40 minutes, with a series of 45 second exposures.  For my night photography, I prefer to work with the illumination of the moon, so you really can’t leave the camera open for long periods of time or the sky will just wash out and or you will only pick up the brightest stars.  Stacking allows you to have much more control of your environment also.

In the past with Canon or Nikon, I would use the remotes that had the built in interval timer.  You need to use the timer for two settings, length of exposure and interval.  The interval is always 1 and the exposure varies depending on the amount of moonlight.   Using the Nikon MC-36 remote, this is easy to do.  Using the built in interval timer on the camera is not.  You can set the interval timer to do 1 interval and a certain number of frames, but the time relies on the cameras set shutter speed for the length of the exposure.  Thus the longest exposure will be 30 seconds and most times at night with stacks that is not long enough.  So the built in timer is not an option.  The time lapse timer has the same shutter speed limitation, requiring the camera to not be in blub mode.  However I have found a new solution from the folks over in China that should work.  A converter that allows the MC-36 to plug in to the port where you plug in the MC-DC2.

MC-30 to MC-DC2 converter

MC-30 to MC-DC2 converter

If this works as advertised a photographer should be able to use all of the functions of the MC-36 on the D600.  I have ordered one and will test it soon to make sure.  If it won’t work or all the functions don’t work, then for me all bets are off for the D600.  I will report back as soon as this converter arrives.

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