Medium Format Astro Photography - Fuji GFX 100s

[maddogmurph]

I've done a fair amount of Astro Photography. The only results that have truly impressed me are utilizing a star tracker, but this is often times impossible for a number of reasons (clouds, low valleys with reference stars unavailable, or challenges with taking heavy balancing gear into the back country).

I usually carry full format into the back country for a number of reasons. I've found the Cannon R5 is essentially useless at night, and the D850 provides the best results shooting wide open (F2.8, 20-25 seconds, between 14-28MM on the Sigma or Zeiss 15mm) around iso 400 (or 6400).

My first Fuji question is, are any large format lenses adaptable to the GFX 100s with the Cambo to get an extra stop of light? The best Fuji has in the lineup is 23mm F4.

Second question: What are best settings and practices for night shooting with this camera?

The example star tracked of what my goal is: https://www.flickr.com/photos/130403473@N07/51146175297/in/dateposted-public/

[Balafre]

What a beautiful photo !

[kers]

+1 impressive night scene..

[Joe Towner]

EF lens with the 'EF-GFX Smart Expander'? Have you tried the Zeiss 15mm on your GFX?

[BernardLanguillier]

Out of curiosity why did you find the R5 useless for night photography?

Sensor issues?

Cheers,
Bernard

[maddogmurph]

EF lens with the 'EF-GFX Smart Expander'? Have you tried the Zeiss 15mm on your GFX?

I hadn't thought about that. That lens is currently broken, but if it would work, I'd buy another. I was looking at the Laowa recently - but that's also F4. Can you adapt the FF lenses to the GFX ?

[maddogmurph]

Out of curiosity why did you find the R5 useless for night photography?

Sensor issues?

Cheers,
Bernard

Noise. Samples show also lines in the dark areas that are nearly impossible to work with.

[TechTalk]

I hadn't thought about that. That lens is currently broken, but if it would work, I'd buy another.

A Zeiss 15 mm f/2.8 is great for your use mounted on a D850 or some other 35 mm full-frame camera. It has a reasonable f/2.8 aperture and 100° horizontal / 110° diagonal angle of view. I could see replacing it for use on a 35mm full-frame camera. That lens, however, has barely enough image circle diameter (44 mm) to cover 35 mm full-frame format (43.3 mm diagonal). It can't provide the 55 mm image circle diameter that you need to cover a 33 x 44 mm sensor. The Zeiss 15 mm has a very wide angle of view, but the angle of coverage is too narrow for larger sensor sizes.

My first Fuji question is, are any large format lenses adaptable to the GFX 100s with the Cambo to get an extra stop of light? The best Fuji has in the lineup is 23mm F4.

The Fuji GFX 100S sensor size is going to severely limit your choices for a wide-angle lens with a maximum aperture of f/2.8. The only options that immediately come to mind are the Schneider Digitar 28 mm f/2.8 L or the Schneider Schneider PC-Super-Angulon 28mm f/2.8 lenses. Both lenses are discontinued, but are available to purchase used or may be available to rent as well. The PC-Super-Angulon series was offered in a variety of lens mounts.

Both of the Schneider lenses have the speed that you require and image circle diameters in the 60-62 mm range, so there is a small amount of shift available on the GFX 100S. Here's a YouTube video demonstrating the FUJI GFX 100S with the PC-Super-Angulon 28mm f/2.8. A 28 mm lens with the Fuji GFX 33 x 44 mm gives you a 76° horizontal / 89° diagonal angle of view. This is the diagonal equivalent of a 22 mm lens with a 35 mm full-frame format.

The Schneider Digitar 28 mm f/2.8 L is available to rent from Foto Care, an excellent photo dealer in New York City. They list it as an "Apo-Digitar", but I believe Apo is a typo. I'm not aware of an Apo labeled version of this lens.

The Schneider PC-Super-Angulon 28mm f/2.8 in Nikon mount is currently offered for sale used by Lensrentals, an excellent resource for rentals and more. Their blog is very informative and their reputation is outstanding.

[TechTalk]

Can you adapt the FF lenses to the GFX ?

There are a variety of adapters for mounting lenses on the Fuji GFX. The first concern would be whether the lens can cover the 33 x 44 mm sensor which requires the lens to have a minimum image circle of 55 mm. Certainly a number of full-frame PC (Perspective Control) or TS (Tilt-Shift) lenses would have image circles which allow for their movements on the full-frame format and also adequate coverage for the Fuji GFX.

With conventional wide-angle lenses, it becomes doubtful that you'll find the lens coverage needed for the larger 33 x 44 mm sensor. The wider the angle and faster the speed of the lens, the more doubtful it becomes due to the inherent increase in size, weight, cost, and complexity of design. This is also why the choice of fast wide-angle lenses for the larger GFX sensor is so limited.

There are adapters for lenses which use a low-power teleconverter lens to enlarge the image circle like the EF-GFX Smart Expander 1.26x , but that will increase the focal length by 1.26x and reduce lens speed by 2/3 of a stop. So, focal length and lens speed are both going in the wrong direction for your needs.

[TechTalk]

Second question: What are best settings and practices for night shooting with this camera?

The link below may be helpful. It sounds like you have discovered best practices thru your own experience. Still, the link may be helpful to others interested in opening up the beauty of the night sky in their images. The website has other articles which may be of interest as well.

https://www.lonelyspeck.com/milky-way-exposure-calculator

[TechTalk]

Another option is a focal length reducing adapter also known as a "speed booster". For instance the Metabones Hasselblad V Lens to GFX Speed Booster 0.71x would convert a Hasselblad Distagon 40 mm f/4 into a 28 mm f/2.8 lens. A Hasselblad Distagon 50 mm f/2.8 would be converted into a 36 mm f/2 lens.

The adapter sells for $899. The lenses would have to be sourced on the used market. You may be able to find either the adapter or lenses available to rent as well.

http://www.hasselbladhistorical.eu/Hasselblad V Lens Data Sheets

[TechTalk]

I was looking at the Laowa [15 mm] recently - but that's also F4.

Laowa (Venus Optics) is producing some very interesting lenses! For full-frame mirrorless cameras, they produce the Laowa 15mm f/2 Zero-D lens. Being two stops faster makes it a great lens for astrophotography. Here is a Flickr sample gallery of images from the lens

https://www.lonelyspeck.com/Laowa 15mm f/2 Zero-D Lens Astrophotography Review

The even faster, and more expensive, lens for your Nikon D850 and other full-frame SLR cameras is the Sigma 14mm F1.8 DG HSM | Art lens which is also a remarkable lens for astrophotography!

https://www.dpreview.com/astrophotography-with-the-sigma-14mm-f1-8-art-lens

[maddogmurph]

Laowa (Venus Optics) is producing some very interesting lenses! For full-frame mirrorless cameras, they produce the Laowa 15mm f/2 Zero-D lens. Being two stops faster makes it a great lens for astrophotography. Here is a

The even faster, and more expensive, lens for your Nikon D850 and other full-frame SLR cameras is the Sigma 14mm F1.8 DG HSM | Art lens which is also a remarkable lens for astrophotography!

I'm interested in trying these, perhaps I'll find a place to rent. I have the Nikon native 24mm F1.4 and have found the coma to be relatively terrible at anything below F2.5, however the additional little bit of light is helpful. Everything like that helps in astro photography, but nothing replaces shooting Iso 200, for 5 minutes with a tracker... I have yet to do the method of stacking many 8 second shots, but I've heard that provides better results as well.

[TechTalk]

It will be interesting to see how your work evolves. I hope that you'll share your results.

Sorry that I could only think of a few 28 mm f/2.8 options for your Fuji GFX 100S. Perhaps others can suggest additional options for you.

The use of focal reducers is an interesting option for astrophotography. Making lenses faster, wider, and in some respects better with an adapter is a neat optical trick!

[BernardLanguillier]

Noise. Samples show also lines in the dark areas that are nearly impossible to work with.

Thanks for the feedbacks.

This is indeed awful. Terrible results.

Cheers,
Bernard

[maddogmurph]

It will be interesting to see how your work evolves. I hope that you'll share your results.

https://www.flickr.com/photos/130403473@N07/52763212786/in/dateposted-public/
https://www.flickr.com/photos/130403473@N07/52139366310/in/dateposted-public/
https://www.flickr.com/photos/130403473@N07/52752556436/in/dateposted-public/

Fortunately for me, the F4 I've found is plenty fast enough for night photography with the Fuji GFX 100s, and I haven't needed to try to adapt a F2.8 lens to the camera - as an update.