Franz Kerschbaum

Franz Kerschbaum

Lives in Austria Austria
Works as a Astronomer
Joined on Apr 2, 2001

Comments

Total: 62, showing: 1 – 20
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On article Heavy hitter: Sony FE 24-70mm F2.8 GM first shots (337 comments in total)
In reply to:

Franz Kerschbaum: Why can RAW be not RAW? Its really bad for some application like Astronomy when such corrections (e.g. vignetting) are already applied. We have our own, controled measures to do it. This tendency is really fustrating

We use IRAF, MIDAS, and typically Phyton based pipelines directly developed for our ground (e.g. ESO VLT) or space based instrumentation (e.g. ESA Herschel). For Acquisition and some quick look analysis on our smaller student project telescopes (60, 80 and 150cm) we have MaximDL with the different SBIG cameras. (concerning flats for camera lenses, I just recently saw that more and more amateurs use these flatfield boxes they have for the telescopes - not so expensive and complex. Sensor dust flat fielding is a must for most of them outside the ideal world!)

Direct link | Posted on Feb 8, 2016 at 11:12 UTC
On article Heavy hitter: Sony FE 24-70mm F2.8 GM first shots (337 comments in total)
In reply to:

Franz Kerschbaum: Why can RAW be not RAW? Its really bad for some application like Astronomy when such corrections (e.g. vignetting) are already applied. We have our own, controled measures to do it. This tendency is really fustrating

Great AstroStan! What product do you offer? We get often requests by amateurs for such products. Besides our day/nighttime business there is not much to argue or fight. I only mentioned my profession in order to avoid getting too much answers telling me the very basics of astronomical image processing (something I do for space telescopes in real-time on board systems). Its not that I need to use DSLR/MILC cameras for my astro work but its a wonderful reality that amateur astronomy has these widespread multi-purpose tools which allow them to enjoy their hobby. For this a wider choice of raw processing levels would be beneficial. You gave the old Nikon problem yourself. It does not cost a fortune for the camera company. This is nothing against Sony but I am allergic against this tendency to reduce the freedom of the user. Yes, do the best "cooking" adopted to lenses and whatever when the customer demands it but at least for the more professional cameras allow us to choose!

Direct link | Posted on Feb 7, 2016 at 18:34 UTC
On article Heavy hitter: Sony FE 24-70mm F2.8 GM first shots (337 comments in total)
In reply to:

Franz Kerschbaum: Why can RAW be not RAW? Its really bad for some application like Astronomy when such corrections (e.g. vignetting) are already applied. We have our own, controled measures to do it. This tendency is really fustrating

Only to make it clear, I am professional astronomer and space instrumentation developer. I know the compromises the manufactorers have to make. Nevertheless, the less brewing they do they easier it is for e.g. amateur astronomers to use the DSLRs for their work (the early Nikons as a bad and Canons as a good example). It would be so easy for them to include a "rawer" mode but they are too afraid of exposing they unprocessed data for testing. (and I know its a small market)

Direct link | Posted on Feb 7, 2016 at 15:24 UTC
On article Heavy hitter: Sony FE 24-70mm F2.8 GM first shots (337 comments in total)

Why can RAW be not RAW? Its really bad for some application like Astronomy when such corrections (e.g. vignetting) are already applied. We have our own, controled measures to do it. This tendency is really fustrating

Direct link | Posted on Feb 6, 2016 at 16:59 UTC as 45th comment | 10 replies
On article Sigma 20mm F1.4 'Art' lens real-world sample gallery (135 comments in total)

Have the lens now for some weeks and quite happy with it on my 5D3. Fantastic light sucker especially in the x-mas time. Did a very consistent MFA with the dock and had -6- -8 which is in line with my other two art lenses (35 and 50). It focuses quite fast even in low light. As an astronomer I tested it already at stars and it is flawless at 4 and good at 2.8 which is really an achivement. DXO pro 10 already has a good profile to correct for the aberrations.
Here are a few RAW images at 1.4, 2.0, 2.8 and 4.0 (with corresponding exposure times to have same exposure level).
https://db.tt/eOEUWMS8

At 1.4 vignetting is very strong and visible when having high background as in my foggy urban case). There is no significant field curvature where focusing at the edges would help. The pics where focused typically halfway from the centre using liveview. The second zip contains dxo developed (only optics correction and vignetting) jpgs:

https://db.tt/kG7o3XXV

Direct link | Posted on Jan 29, 2016 at 09:00 UTC as 20th comment
In reply to:

Franz Kerschbaum: Everybody who did under waterphotography knows that you have to position the flash as far as possible away from the optical axis to reduce light scatter from particles in the water. Lets hope there is a connector for external ones and not only this hump on the lens...

You are right. The title says only "underwater compact". What a waste of time and effort.

Direct link | Posted on Jan 22, 2016 at 09:19 UTC
In reply to:

Franz Kerschbaum: Everybody who did under waterphotography knows that you have to position the flash as far as possible away from the optical axis to reduce light scatter from particles in the water. Lets hope there is a connector for external ones and not only this hump on the lens...

"Audi Design" as they wrote ...

Direct link | Posted on Jan 21, 2016 at 17:09 UTC
In reply to:

Franz Kerschbaum: Everybody who did under waterphotography knows that you have to position the flash as far as possible away from the optical axis to reduce light scatter from particles in the water. Lets hope there is a connector for external ones and not only this hump on the lens...

No, but I would expect to have the flash not on the worst place. Even a regular position as on any other compact would be better and why not a flash connector? Nobody sked for a permanent "giant arm". For that price I would expect some basics. Its a pity since many wait for an APS-C waterproof cam.

Direct link | Posted on Jan 21, 2016 at 16:39 UTC

Everybody who did under waterphotography knows that you have to position the flash as far as possible away from the optical axis to reduce light scatter from particles in the water. Lets hope there is a connector for external ones and not only this hump on the lens...

Direct link | Posted on Jan 21, 2016 at 12:13 UTC as 32nd comment | 7 replies
On article Nikon's New D5 and D500 Push the Boundaries of DSLR (733 comments in total)

No pushing in the Video domain: http://www.eoshd.com/2016/01/nikon-d5-versus-canon-1d-c-cinematic-4k-video-wins/

Direct link | Posted on Jan 11, 2016 at 08:49 UTC as 34th comment | 3 replies

Great entry! Now for a m4 ...

Direct link | Posted on Oct 13, 2015 at 07:10 UTC as 48th comment
On article Canon EOS M3 real-world samples (152 comments in total)

Since two weeks or so my M3 pics can also be raw processed in DXO10pro. With the 5D3 presetting applied it seamlessly fits into mixed productions with my 5d3 and 7D2. Love it also for the 11-22 which is clued on the m3 (only the 100mm IS macro replaces it from time to time!). Had all three cams on a Svabard trip the last weeks and could not be satisfied more.

Direct link | Posted on Sep 11, 2015 at 13:26 UTC as 22nd comment

Here I hope for a soft copy!

Direct link | Posted on May 2, 2015 at 21:23 UTC as 130th comment
On article New samples from the Sigma 24mm F1.4 DG HSM Art lens (232 comments in total)
In reply to:

Peter Togel: O wonder how the autofocus works on this one. The 50mm Art Autofocus drives me crazy...

Have both the S35A and the S50A and use them on eos 5D2, 5D3, 7D, 450D and have no focusing problems whatsoever. The microadjustment via the USB dock worked like charm. For unfortunate customers having a bad copy I would recommend to return them or let them be checked (happend to me with my EF14/2.8II and the now gone EF50/1.4).

Direct link | Posted on Feb 26, 2015 at 15:46 UTC
In reply to:

jtan163: Carbon fibre body?
Wireless?
Hmm, well according to about 50% of the Nikon FX forum it must be an amateur model.
Pro cameras are made of magnesium alloy and wireless is just an affection for amateurs and soccer parents...
I'm just saying.

I wonder if I will be able to use my Canon LP-E6N battery. I am quite invested in these fantastic power sources and dont want to loose too much money when switching.

Direct link | Posted on Feb 25, 2015 at 11:51 UTC
In reply to:

jtan163: Carbon fibre body?
Wireless?
Hmm, well according to about 50% of the Nikon FX forum it must be an amateur model.
Pro cameras are made of magnesium alloy and wireless is just an affection for amateurs and soccer parents...
I'm just saying.

Does it have a print button?

Direct link | Posted on Feb 24, 2015 at 12:01 UTC
In reply to:

Biowizard: I wonder whether DJI will source its camera technology from Olympus? Might even be able to do away with the expensive and cumbersome external 3-axis gimble, if they employed Oly's E-Mx 5-axis IS sensor!

It makes a lot more sense to jiggle a sensor about, than to jiggle the entire camera (as at present on, for example, the Phantom Vision +).

And I would LOVE to be able to use rectilinear lenses with normal fields of view (say 35mm in full-frame terms), rather than the omnipresent fish-eye lenses of today's "action" cameras.

Brian

Dont forget the amount of correction possible (the total amplitude) in a sensor stabilisation system ist MUCH smaller than what is needed and provided by a gimbal system used on copters .. So there is nothing to save! Sorry.

Direct link | Posted on Feb 17, 2015 at 12:45 UTC
In reply to:

Joe Ogiba: DPR: "Nikon aims for the stars with the D810A, world’s first full-frame astrophotography camera"

Really ?
"The Sony A7s is going to be the next big thing with astrophotography."
http://www.jtwastronomy.com/products/modified_sony_a7s.html

http://petapixel.com/2014/07/30/sony-a7s-astrophotography-review/

Many of us H alpha modified there Canon full frames for 300-400US$ ... Here in Austria even the Canon service center does this on request ...

Direct link | Posted on Feb 11, 2015 at 11:43 UTC
In reply to:

Edgar_in_Indy: The killer feature would be if the camera was able to use a sensor stabilization system together with GPS to track and compensate for star movement, like Pentax does with their DSLR's. But tragically, according to the terms of the Geneva Convention, Nikon and Canon are banned from offering any kind of sensor stabilization, and the derivative features, on any of their DSLR cameras.

At least I assume that's the case, since they seem dead-set on denying their loyal customers the many virtues of sensor shift capabilities. Hmmm...I wonder why that would be?

Another nice compact option when traveling! https://www.ioptron.com/index.cfm?select=productdetails&phid=6b0da2fb-2294-4805-bdcb-e534af12c1e2

Direct link | Posted on Feb 11, 2015 at 11:40 UTC
In reply to:

Esign: And where can I get a lightweight foldable travel clockwork tripod? I need some fast shots of Andromeda now.

Quite nice fro up to 135mm lenses ...
https://www.ioptron.com/index.cfm?select=productdetails&phid=6b0da2fb-2294-4805-bdcb-e534af12c1e2

Direct link | Posted on Feb 11, 2015 at 11:37 UTC
Total: 62, showing: 1 – 20
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