Leica Noctilux 50mm or 75mm for Astro work

[Chaipaval]

Advertisement (gone after registration)

Would this make a great lens for star photography?

[nwphil]

you forgot to mention which camera model...

never used the M240 for astro photography, but if I was to, a wider angle would be my choice as it covers more FOV and allows for more exposure time (500/rule) without star trails/streaks

Unless you want star tracks or are mounting it on a startracker .

regarding chromatic aberrations, edge distortion/sharpness, vignetting, the 75 might do a better job than the 50, as in less of all that...

Edited November 1, 2019 by nwphil

[mmradman]

Leica Noctilux 50mm is an art/photo reportage lens for low light and extreme shallow DOF (call it bokeh if you like), not sure if its corrected for this type of photography, more recent 75mm is probably better in that regard. One can always try in the search of the infinite wisdom. 

For Astro type shooting in 50mm to 75mm FL range on full frame Nikon Z 58mm f0.95 Noct and previous Nikon F 58mm 1.2 Noct which is/was corrected for point lights at maximum aperture is probably the one to consider.

[FrozenInTime]

2 hours ago, mmradman said:

. 

For Astro type shooting in 50mm to 75mm FL range on full frame Nikon Z 58mm f0.95 Noct and previous Nikon F 58mm 1.2 Noct which is/was corrected for point lights at maximum aperture is probably the one to consider.

The classic 58/1.2 Noct Nikkor, I found to be very poor at rendering star scapes:

The 50/1 Noctilux I had at the same time showed tightly defined point sources over 2/3 of image, with increasing butterfly coma in the outer zones.

The 58/1.2 Noct Nikkor showed a consistent glow ball aberration across the whole image, but points  just grew and grew in size as exposure increased, which resulted in a trade off between faint objects and bright stars. To eliminated the diffuse ball like aberration, the lens needed stopped down to f/2.8.

Overexposed bright stars on the Noctilux remained tight points allowing a good balance of faint and bright objects at all apertures.

The new Z 0.95 Noct Nikkor lens looks like a tour de force, great for cinematographers and astrophotographers, but way to large for general photo use.

On (21...35) vs 50 vs 75 , for unguided work the wider lenses can often provide an interesting view incorporating foreground landscape features.

[darylgo]

Never tried the 50mm Noctilux for stars, the 21mm Summilux suffers from coma and I would think the 50 Noctilux would also.  The 50mm Summilux Asph works well.  8 sec f1.4 iso 3200.

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

 for stars and stitching.  

[IkarusJohn]

I’ve always thought wide for astro-photography,  but then, I’m new to this.

[darylgo]

Advertisement (gone after registration)

42 minutes ago, IkarusJohn said:

I’ve always thought wide for astro-photography,  but then, I’m new to this.

Wides are used mostly, for stitching the focal lengths of 50mm and 75mm are excellent.  Exposure times must decrease with longer focal lengths to avoid star movement, wides have this advantage among others.  Not unlike many rules breaking them can lead to creative results........or often-time disasters :-)   

[FrozenInTime]

42 minutes ago, darylgo said:

Wides are used mostly, for stitching the focal lengths of 50mm and 75mm are excellent.  Exposure times must decrease with longer focal lengths to avoid star movement, wides have this advantage among others.  Not unlike many rules breaking them can lead to creative results........or often-time disasters 🙂   

If I remember :

The rule of thumb used to be to keep the exposure under 60/focal-length seconds to avoid star trails. With more megapixels resolution than with fast film, that ratio might now be nearer 40/focal-lenght.

[FrozenInTime]

9 hours ago, FrozenInTime said:

If I remember :

The rule of thumb used to be to keep the exposure under 60/focal-length seconds to avoid star trails. With more megapixels resolution than with fast film, that ratio might now be nearer 40/focal-lenght.

edit : that should be ~600/focal-length - around 10 seconds for 50mm.

[Chaipaval]

Thanks to everyone for all the useful posts which has got me thinking. Firstly I use a Leica because my simple/addled brain understands a large % of the functions available. Secondly and importantly the lenses produce great images. I have a Leica 240 and a Leica Monochrom. Neither camera allows me full control over length of exposure. I am also somewhat adverse to stacking images but realise I need to just go with it. I have been using an Elmarit 2.8/28mm but recognise the limitations of its light gathering ability and the Leica M's restricted length of exposure. I could invest in a motorised polar mount but am resistant to the added complications. 

My limited understanding calculates the light gathering of a Leica Noctilux 75mm at f1.25 = 60. This is significantly better than the Leica Summilux f1.4/50mm @ 36 and my Elmarit at 10. However a Noctilux is rather heavy on both camera and pocket. An alternative might be the Summilux f1.4/75mm @ 54 - close to the Noctilux and lighter on tripod and pocket. Any thoughts?

I see Daryl's excellent image from the Summilux 1.4/50 and was surprised at the High ISO. Could it be crisper with a much lower ISO and longer exposure. How might this get incorporated into the 600/focal length calculation to avoid star trails?

[darylgo]

6 hours ago, FrozenInTime said:

edit : that should be ~600/focal-length - around 10 seconds for 50mm.

400-600, from the sources I've read.  If critical the images can be viewed in the field (not always easy in the dark and pushing buttons without a flashlight or losing dark adaptation) for star trails and iirc there are programs to turn trails into points. 

3 hours ago, Chaipaval said:

Thanks to everyone for all the useful posts which has got me thinking. Firstly I use a Leica because my simple/addled brain understands a large % of the functions available. Secondly and importantly the lenses produce great images. I have a Leica 240 and a Leica Monochrom. Neither camera allows me full control over length of exposure. I am also somewhat adverse to stacking images but realise I need to just go with it. I have been using an Elmarit 2.8/28mm but recognise the limitations of its light gathering ability and the Leica M's restricted length of exposure. I could invest in a motorised polar mount but am resistant to the added complications. 

My limited understanding calculates the light gathering of a Leica Noctilux 75mm at f1.25 = 60. This is significantly better than the Leica Summilux f1.4/50mm @ 36 and my Elmarit at 10. However a Noctilux is rather heavy on both camera and pocket. An alternative might be the Summilux f1.4/75mm @ 54 - close to the Noctilux and lighter on tripod and pocket. Any thoughts?

I see Daryl's excellent image from the Summilux 1.4/50 and was surprised at the High ISO. Could it be crisper with a much lower ISO and longer exposure. How might this get incorporated into the 600/focal length calculation to avoid star trails?

The Summilux image was underexposed and Leica is quite challenging to use for astro.  My primary camera for night is a Canon.  Nikon, Canon and Sony would give excellent results.  

Coma is the primary limiting issue for lenses rendering stars as points.  The 75mm Summilux would need to be tested, an old Mandler design, I would be surprised if coma isn't an issue but I haven't tested it.  

Astro is pushing cameras and lenses to their limits.  As you mention star trails or motion is the time limit, sensor sensitivity requires high iso, lenses must be corrected well for coma and at least f2.8.  Perhaps the newer cameras overcome some of these limits with their improved sensor noise and you could use a tracker to allow longer times, the lenses are what they are and can not be changed.  

Grant Collier's "Collier's Guide to Night Photography in the Great Outdoors" has a wealth of information, recommended reading and well written with all the formulas and some post processing recommendations.