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Sony A7 III w/ Samyang 135mm Low Light Testing
Aug 21, 2019 14:33:24   #
bwana Loc: Bergen, Alberta, Canada
 
I acquired a Sony A7 III (24 MP, 6000x4000 resolution) about two months ago and have been playing with terrestrial as well as astro/nightscape photography. I consider myself still in testing mode, not so much with A7++'s (since I've owned an A7S, A7R, A7 II and A7R II) but simply to see what the A7 III is capable of.

I previously shot a suite of nightscape images with ISO 800 all the way up to ISO 204800 for the fun of it. Since the A7 III is now the reigning low light performer, even a step ahead of the A7S, at least according to DxO Mark's numbers, it was time to shoot some astro-images.

I set up the A7 III w/ a Samyang 135mm lens at f/3.5 lens on a tripod. To keep star trailing to a minimum (according to the 500 Rule) I set exposure to 2.5 sec. and ISO to Auto (w/ a max. ISO limit of 51,200). I then proceeded to shoot three regions on the Milky Way; Cassiopeia (w/ PacMan nebula), Deneb (w/ North America/Pelican nebulas) and an area around the Dumbbell nebula (M57).

Due to the short exposure the camera chose an ISO in the range of 32,000-40,000 over the three imaging sessions.

I shot at least 50 subs for each session (~125-150 sec. total per session) and processed them in PixInsight and Lightroom. I did not apply any noise reduction (in-camera or in postprocessing) and did not do any sharpening. I'm actually quite amazed with the results even considering I'm a long time full spectrum modded A7S user and the A7 III is a stock camera, i.e.: not modded.

A couple of pix captured are attached; be sure to look at the Download image. For anyone interested in my other low light test shots, my A7 III testing album is at: https://www.flickr.com/photos/brianallan/sets/72157710124679096/.

The above album does NOT contain the other ~1,000 terrestrial pix I've shot in the past couple of months.

Enjoy!

bwa

MW_Deneb(52x2.5sec@ISO32,000-40,000)_MStretch_ABE
MW_Deneb(52x2.5sec@ISO32,000-40,000)_MStretch_ABE...
(Download)

MW_Dumbbell(62x2.5sec@ISO32,000-40,000)_ABE_MStretch_ABE
MW_Dumbbell(62x2.5sec@ISO32,000-40,000)_ABE_MStret...
(Download)

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Aug 21, 2019 16:56:16   #
JimH123 Loc: Morgan Hill, CA
 
bwana wrote:
I acquired a Sony A7 III (24 MP, 6000x4000 resolution) about two months ago and have been playing with terrestrial as well as astro/nightscape photography. I consider myself still in testing mode, not so much with A7++'s (since I've owned an A7S, A7R, A7 II and A7R II) but simply to see what the A7 III is capable of.

I previously shot a suite of nightscape images with ISO 800 all the way up to ISO 204800 for the fun of it. Since the A7 III is now the reigning low light performer, even a step ahead of the A7S, at least according to DxO Mark's numbers, it was time to shoot some astro-images.

I set up the A7 III w/ a Samyang 135mm lens at f/3.5 lens on a tripod. To keep star trailing to a minimum (according to the 500 Rule) I set exposure to 2.5 sec. and ISO to Auto (w/ a max. ISO limit of 51,200). I then proceeded to shoot three regions on the Milky Way; Cassiopeia (w/ PacMan nebula), Deneb (w/ North America/Pelican nebulas) and an area around the Dumbbell nebula (M57).

Due to the short exposure the camera chose an ISO in the range of 32,000-40,000 over the three imaging sessions.

I shot at least 50 subs for each session (~125-150 sec. total per session) and processed them in PixInsight and Lightroom. I did not apply any noise reduction (in-camera or in postprocessing) and did not do any sharpening. I'm actually quite amazed with the results even considering I'm a long time full spectrum modded A7S user and the A7 III is a stock camera, i.e.: not modded.

A couple of pix captured are attached; be sure to look at the Download image. For anyone interested in my other low light test shots, my A7 III testing album is at: https://www.flickr.com/photos/brianallan/sets/72157710124679096/.

The above album does NOT contain the other ~1,000 terrestrial pix I've shot in the past couple of months.

Enjoy!

bwa
I acquired a Sony A7 III (24 MP, 6000x4000 resolut... (show quote)


Very nice results. I am going to have to try this experiment. I sold my Sony A99 and now have the Sony A7iii too. And I have the Rokinon version of the 135mm lens. And it produces nice looking stars. I am sure your sky is darker than mine though.

For those that aren't aware, there is no difference in the Samyang and Rokinon lenses.

Here is a shot of the California Nebula taken with the Rokinon 135mm lens, but I used an Olympus EM5ii that was modded for full spectrum to show the way it is producing nice round stars. With the 2X crop factor of this camera, this is really the FOV of a 270mm lens. This was a stack of 29 images that I had stacked in DSS and then processed in Photoshop to produce this. These images were taken at ISO 1600 and for 15 sec each. I didn't write down what f-stop I used. It may have been wide open. And the camera was on a mount that was tracking. One thing to watch is exposure time as it is possible to over expose and get unusable results. In the individual images, the CA Nebula was not very visible, but after stacking, I was able to stretch it. The cropping was very minimal.

I also have the Rokinon/Samyang 14mm, 24mm, 50mm and 85mm lenses, and they are great for astrophotography too.

The 2nd image is to show how the 24mm lens handles stars, this time Capella. Again, the same Olympus EM5ii, but this time a not perfectly clear night. This one is minimally processed, not stacked and no noise reduction.


(Download)


(Download)

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Aug 21, 2019 17:26:09   #
bwana Loc: Bergen, Alberta, Canada
 
JimH123 wrote:
Very nice results. I am going to have to try this experiment. I sold my Sony A99 and now have the Sony A7iii too. And I have the Rokinon version of the 135mm lens. And it produces nice looking stars. I am sure your sky is darker than mine though.

For those that aren't aware, there is no difference in the Samyang and Rokinon lenses.

Here is a shot of the California Nebula taken with the Rokinon 135mm lens, but I used an Olympus EM5ii that was modded for full spectrum to show the way it is producing nice round stars. With the 2X crop factor of this camera, this is really the FOV of a 270mm lens. This was a stack of 29 images that I had stacked in DSS and then processed in Photoshop to produce this. These images were taken at ISO 1600 and for 15 sec each. I didn't write down what f-stop I used. It may have been wide open. And the camera was on a mount that was tracking. One thing to watch is exposure time as it is possible to over expose and get unusable results. In the individual images, the CA Nebula was not very visible, but after stacking, I was able to stretch it. The cropping was very minimal.

I also have the Rokinon/Samyang 14mm, 24mm, 50mm and 85mm lenses, and they are great for astrophotography too.

The 2nd image is to show how the 24mm lens handles stars. Again, the same Olympus EM5ii.
Very nice results. I am going to have to try this... (show quote)

You're missing the Samyang 35mm; the best of the lot (and yes, I have all the same ones as well as the 6.5 fisheye).

bwa

Milky Way (mosaic of 13 subs w/ 35mm in Affinity Photo)
Milky Way (mosaic of 13 subs w/ 35mm in Affinity P...
(Download)

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Aug 21, 2019 17:31:45   #
JimH123 Loc: Morgan Hill, CA
 
bwana wrote:
You're missing the Samyang 35mm; the best of the lot (and yes, I have all the same ones as well as the 6.5 fisheye).

bwa


Another nice one. I had actually bought a used 35mm and the focusing mechanism was somehow damaged and hard to turn, so I sent it back.

Here is the 85mm with the Sony A99. Again, I like how the stars turn out with these lenses.

And the 2nd is the 50mm with the Sony A99. Again, nice stars.

I could also show you some other lenses with not so nice stars, but I think I will just hide those ones.


(Download)


(Download)

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Aug 21, 2019 17:37:17   #
bwana Loc: Bergen, Alberta, Canada
 
JimH123 wrote:
Another nice one. I had actually bought a used 35mm and the focusing mechanism was somehow damaged and hard to turn, so I sent it back.

Here is the 85mm with the Sony A99. Again, I like how the stars turn out with these lenses.

All the Samyang lenses do an excellent job; specially for the $$$'s!

I have a much more expensive Sigma 35mm f/1.4 Art lens and it has to be stopped down to about f/2.8 to match Samyang 35mm performance. Of course the Sigma is autofocus but AF is not of much use for astrophotography.

bwa

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Aug 21, 2019 17:42:26   #
JimH123 Loc: Morgan Hill, CA
 
bwana wrote:
All the Samyang lenses do an excellent job; specially for the $$$'s!

I have a much more expensive Sigma 35mm f/1.4 Art lens and it has to be stopped down to about f/2.8 to match Samyang 35mm performance. Of course the Sigma is autofocus but AF is not of much use for astrophotography.

bwa


It is important to point all this out. Many lenses that are really good for terrestrial objects just don't cut it for stars.

I am going to show a lens not doing so good. Here is the legendary Asahi Pentax Takumar 50mm f1.4. This is the the hard to find 7 element version. This is the one that was designed to beat the Planar lens. And it did. And as soon as they got the review they were looking for that confirmed that it was sharper than the Planar lens, this lens was dropped from production, and the cheaper to manufacture 8 element was released. Hit download and look along the edges, especially the far right brightest star. This is not unusual.

And in case you want to see the 8 element version, look at the 2nd image. Not really any better, but different. The trees are out of focus since I was tracking.


(Download)


(Download)

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Aug 21, 2019 18:02:54   #
bwana Loc: Bergen, Alberta, Canada
 
JimH123 wrote:
It is important to point all this out. Many lenses that are really good for terrestrial objects just don't cut it for stars.

I am going to show a lens not doing so good. Here is the legendary Asahi Pentax Takumar 50mm f1.4. This is the the hard to find 7 element version. This is the one that was designed to beat the Planar lens. And it did. And as soon as they got the review they were looking for that confirmed that it was sharper than the Planar lens, this lens was dropped from production, and the cheaper to manufacture 8 element was released. Hit download and look along the edges, especially the far right brightest star. This is not unusual.
It is important to point all this out. Many lense... (show quote)

I have the SMC Pentax-F 50mm f/1.7 and the SMC Pentax-F 35-105mm f/4-5.6 from my days as a photojournalist with a Pentax Spotmatic 35mm film camera. They work amazing well adapted on Sony A7++ bodies! The 'ol Canon FD 50mm f/1.4 is equally good.

bwa

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Aug 21, 2019 18:08:57   #
JimH123 Loc: Morgan Hill, CA
 
bwana wrote:
I have the SMC Pentax-F 50mm f/1.7 and the SMC Pentax-F 35-105mm f/4-5.6 from my days as a photojournalist with a Pentax Spotmatic 35mm film camera. They work amazing well adapted on Sony A7++ bodies! The 'ol Canon FD 50mm f/1.4 is equally good.

bwa


I actually have a collection of old Takumar lenses. Some of the longer focal lengths look reasonably good with stars.

Can't help myself. I also collect old Minolta lenses too.

Many years ago, when I was in the Navy, I bought my father a Pentax Spotmatic II. I am guessing it was 1972 when I was in Japan. He tromped all over the hills of northwestern Pennsylvania for years taking pictures of anything that moved. I have a box of his old slides sitting up in a closet right now. Over 20 years ago, my son was using that old Spotmatic in high school for a photography class, and it got stolen from his locker. Too bad, that old camera had lots of fond memories.

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Aug 21, 2019 18:34:29   #
bwana Loc: Bergen, Alberta, Canada
 
JimH123 wrote:
I actually have a collection of old Takumar lenses. Some of the longer focal lengths look reasonably good with stars.

Can't help myself. I also collect old Minolta lenses too.

Many years ago, when I was in the Navy, I bought my father a Pentax Spotmatic II. I am guessing it was 1972 when I was in Japan. He tromped all over the hills of northwestern Pennsylvania for years taking pictures of anything that moved. I have a box of his old slides sitting up in a closet right now. Over 20 years ago, my son was using that old Spotmatic in high school for a photography class, and it got stolen from his locker. Too bad, that old camera had lots of fond memories.
I actually have a collection of old Takumar lenses... (show quote)

I have a goodly number of Minolta AF (and Sony A mount) lenses, from the autofocus 500mm reflector all the way down. I use them extensively on the A7R II and A7 III bodies with Sony's LA-EA4 & EA2 adapters; great glass! One of my photography buddies calls it my Minolta fleet...

bwa



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Aug 21, 2019 18:55:43   #
JimH123 Loc: Morgan Hill, CA
 
bwana wrote:
I have a goodly number of Minolta AF (and Sony A mount) lenses, from the autofocus 500mm reflector all the way down. I use them extensively on the A7R II and A7 III bodies with Sony's LA-EA4 & EA2 adapters; great glass! One of my photography buddies calls it my Minolta fleet...

bwa


Yep. I have the 500mm reflex. And I have the LA-EA3 and LA-EA4. And a whole bunch more. And they all work great. I still would like to see Sony redo the LA-EA4 and make one without the SLT mirror, but with the screw drive so that the E-Mount bodies would have more than 15 focus points. Don't know why they haven't done this? There are a lot of true blue, dyed in the wool, Minolta users out there that if Sony ever wants to get them to come to mirrorless, they have to throw them a bone. I keep hoping that there might be a surprise come Aug 29/30, when Sony announces the two new APS-C E-Mount bodies, that such an adapter might be offered also. Reason being is that Sony has neglected the APS-C market for some years now as they filled out the full frame lens offerings. And now, the first APS-C sized bodies in quite a while. But there are not a lot of new lenses for the APS-C bodies. And that is where such an adapter would make sense. Not only that, I also think they should design their own speed booster to go with it so that all those marvelous Minolta lenses could be used with these new bodies. Just me thinking, but I think it would go a long ways towards unruffling the feathers of the long time Minolta crowd.

By the way, I do not have a collection of native Sony full frame E-Mount lenses. They are really, really good. But really, really expensive. I do have some Tamrons that have built in AF motors and they work with the LA-EA3 -- the 15-30, the 24-70 and the 150-600. But the 70-200 still is screw drive, so I have to use the LA-EA4 for that one.

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Aug 21, 2019 19:14:57   #
bwana Loc: Bergen, Alberta, Canada
 
JimH123 wrote:
Yep. I have the 500mm reflex. And I have the LA-EA3 and LA-EA4. And a whole bunch more. And they all work great. I still would like to see Sony redo the LA-EA4 and make one without the SLT mirror, but with the screw drive so that the E-Mount bodies would have more than 15 focus points. Don't know why they haven't done this? There are a lot of true blue, dyed in the wool, Minolta users out there that if Sony ever wants to get them to come to mirrorless, they have to throw them a bone. I keep hoping that there might be a surprise come Aug 29/30, when Sony announces the two new APS-C E-Mount bodies, that such an adapter might be offered also. Reason being is that Sony has neglected the APS-C market for some years now as they filled out the full frame lens offerings. And now, the first APS-C sized bodies in quite a while. But there are not a lot of new lenses for the APS-C bodies. And that is where such an adapter would make sense. Not only that, I also think they should design their own speed booster to go with it so that all those marvelous Minolta lenses could be used with these new bodies. Just me thinking, but I think it would go a long ways towards unruffling the feathers of the long time Minolta crowd.

By the way, I do not have a collection of native Sony full frame E-Mount lenses. They are really, really good. But really, really expensive. I do have some Tamrons that have built in AF motors and they work with the LA-EA3 -- the 15-30, the 24-70 and the 150-600. But the 70-200 still is screw drive, so I have to use the LA-EA4 for that one.
Yep. I have the 500mm reflex. And I have the LA-... (show quote)

I have the LA-EA2 adapter for all those APS-C lenses I might want to use; however, I primarily use it as a crop mode adapter with any Minolta AF/Sony A lenses that are a little questionable on the edges/corners. It is also a backup for LA-EA4. I could simply set crop mode on the camera with the LA-EA4 but it is nice to have the backup adapter.

I have two actual FE lenses; both so-called kit lenses, the 28-70mm which I use primarily for IR on the A7S and the 24-240mm which was a promotional lens when I bought the A7R II. And yes, sadly, Sony lenses and third party FE lenses are too damned expensive and based on my experience with Sony's 70-200mm f/4 lens no better than any other lenses in the wild! I did have Sony's 70-200mm lens for about a month but found it to be decentered. I asked for an exchange and the dealer refused so I went after a refund and got the total price plus shipping refunded; kinda weird. I bought a used Canon 70-200mm f/2.8 and have had excellent results with it and a Sigma MC-11 adapter.

Ain't photography fun (and a great money pit!)

bwa

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