oscarvdvelde

Lives in Spain Prov. of Barcelona, Catalonia, Spain
Works as a thunderstorm & lightning researcher
Joined on Apr 29, 2006

Comments

Total: 195, showing: 1 – 20
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In reply to:

oscarvdvelde: The photo shows that rnclark (astrophotography forum) is right that color casts should be corrected with subtraction, not by white balance color channel multiplications, which goes horribly wrong.

Just save the image as TIFF and open it in RawTherapee. In the color correction tab, shift the bottom left point in the RGB curves (G and B) halfway to the right, the R a little to the right, and set the black point to 10,000 and the image looks almost normal.

Leaves me wondering why we don't have color subtraction in-camera instead of white balance.

Yes I agree, and I will add a like to your post. In the first image which is discussed in this article, the issue is a veil of added light, so subtraction works. The second image I also tried, and could not be restored this way, as the color shift was apparently produced very differently. Yes, if we subtracted tungsten light, all we get is a darker to black image without light. And yes, a good subtraction would be on the raw linear data before any curve applied, and simply would be a straight line under and parallel to the y=x line.

It seems the eyes certainly do a color correction, easily noticed if you stare in the dark at a screen controlled by f.lux software under 3000K. Or having had sunlight on closed eyes for some minutes. The correction lingers for some minutes while you look away to another scene.

Link | Posted on Mar 2, 2017 at 15:24 UTC

The photo shows that rnclark (astrophotography forum) is right that color casts should be corrected with subtraction, not by white balance color channel multiplications, which goes horribly wrong.

Just save the image as TIFF and open it in RawTherapee. In the color correction tab, shift the bottom left point in the RGB curves (G and B) halfway to the right, the R a little to the right, and set the black point to 10,000 and the image looks almost normal.

Leaves me wondering why we don't have color subtraction in-camera instead of white balance.

Link | Posted on Mar 1, 2017 at 23:21 UTC as 57th comment | 3 replies
On article Throwback Thursday: the Canon EF 24-70mm F2.8L (116 comments in total)

In the sequence 35-70mm, 28-70mm, 24-70mm with a decade difference between them, I am still waiting for 20-70mm zooms to come in this decade :)

Link | Posted on Feb 23, 2017 at 11:27 UTC as 40th comment | 5 replies
On article Extremely dramatic video touts Canon's CMOS technology (196 comments in total)
In reply to:

Shlomo Goldwasser: The voice-over should have been done by The Donald or The Governator.

Terrible. I suppose there is a class "How to use intonation to make mundane things sound incredible".

Link | Posted on Feb 17, 2017 at 15:29 UTC
On article Stunning time-lapse captures the seasons of Norway (65 comments in total)
In reply to:

mezastel: This is an awesome set of timelapse compilations! I do wonder though, why has the author restricted it to a letterbox format instead of sticking to good old-fashioned 16:9. Is it because it provides more opportunities for cropping? Also I visited Norway a few years back and yes, it does look this beautiful.

Such wonderful series and then crop off the top and bottom, it is a pity. Especially for things like aurora.

Link | Posted on Feb 3, 2017 at 00:46 UTC
In reply to:

great Javier: Wihtout dxomark, it s complicated to know how good is fujifilm system :-(

No problem comparing Fuji lenses using LensTip and Photozone.

Link | Posted on Jan 31, 2017 at 16:41 UTC
In reply to:

Terry Breedlove: Trump is about to erase everything Obama has done. His Legacy Lives by the executive order and will die by the executive order. Overnight !

My understanding is that Obama sought bipartisan solutions in his first four years, but the Republicans just did not want him to succeed in anything.
Now Trump is going to undo as much government as possible to help the greedy, which will not benefit the general public, even his voters. I guess he won't care about public debt. The more debt the less government! His followers will accept all his lies and willfully ignoring of inconvenient facts and blame everything on a liberal conspiracy.

Link | Posted on Jan 21, 2017 at 17:45 UTC
In reply to:

turbsy: $450 for a slow 50mm? No thanks Fuji

It autofocuses a lot faster than all the faster adaptable 50mm lenses out there.
It is cheaper per f-stop than the 27mm f/2.8!

Link | Posted on Jan 21, 2017 at 12:55 UTC
In reply to:

falconeyes: Everybody seems to accept that US (NSA) intercepts our private data.
Now with China though, it's a different thing ...
Dear American fellows, Welcome to the world of the rest of us ;)

And today's USA president in control of NSA has not shown much respect for ethics so far...

Link | Posted on Jan 20, 2017 at 13:52 UTC
In reply to:

whtchocla7e: More options is always better but what exactly is the point of the 50mm focal length on small sensor?

But then you could just choose the XF 60mm...

Link | Posted on Jan 19, 2017 at 23:47 UTC
In reply to:

oscarvdvelde: A good thing about the lens is its 0.39m minimum focus distance. Better than my Samyang 50mm F1.2 at 50 cm or the XF 56mm at 70 cm.

It's good for close subjects, very sharp even wide open if focus is nailed. Bokeh sometimes has a doubling effect for subjects at medium distance (maybe this was at f/2 - no EXIF info from the lens). Also I've seen onion rings in out of focus specular highlights. Compared to a Takumar 50mm F1.4 SMC it is more contrasty but the bokeh can show artefacts the old lens does not have.

The lens is also good at f/1.4 at infinity (if you nail focus, quite easy). But stopped down I find field curvature in distant landscape shots, and the focus shifts between wide open and stopped down. This makes finding focus pretty difficult in that situation.

Overall I am happy with that lens, but if the XF 50mm F2.0 has smoother bokeh and sharper and more reliable focusing at infinity, it could be attractive.

Link | Posted on Jan 19, 2017 at 16:02 UTC

A good thing about the lens is its 0.39m minimum focus distance. Better than my Samyang 50mm F1.2 at 50 cm or the XF 56mm at 70 cm.

Link | Posted on Jan 19, 2017 at 10:08 UTC as 12th comment | 4 replies
In reply to:

vinrouge0: I don't really get the focal length though clearly others must have stated differently or Fuji would not have developed it. Clearly OIS is not a priority which surprises me as small stabilised primes would be very appealing to many

50mm (76mm eq.) offers a very useful angle of view, you get a slight compression but still freedom to compose. For some people it is better than 35mm (50mm eq.) which feels too narrow and wide at the same time. The FOV should be familiar to anyone who used 50-200 or 75-300mm lenses in the past. It is good for portraits with some surroundings included, or for tighter portraits of 2 or more persons.

OIS will add to the size and weight of a lens, defeating the purpose of the small lens. They should have added it to the XF 90mm (but... even more weight?), as users often recommend to stay at 1/200th sec or faster exposure.

Link | Posted on Jan 19, 2017 at 10:04 UTC
In reply to:

maxnimo: If 20mm is Super Wide Angle then what's 10mm and 15mm? Ultra wide? Super-duper wide?

20 and 24mm lenses have been called super wide angle. At least at the time I bought a Sigma 20mm F1.8 EX in 2002.

Link | Posted on Dec 29, 2016 at 19:22 UTC
In reply to:

Hanoise: Professional photography is a necessity. This is a clear assassination on the Russian gov representative.
What a photo doesn't do unfortunately, is it doesn't explain the context to any given event, situation, action etc. we see a man holding a gun, pointing his finger to the lord, and another on the floor......lifeless...

Our minds tell us that this is horrible, and indeed it is.

The media know this and give it a title " man kills man and screams allahu Akbar", playing on all our naivety on what is really happening behind the scenes.

Russia sells weapons to ALL the evil rebels and even MORE evil governments around the globe including bashar and his horrible regime! Russia is directly profiting in the death and destruction of children, women, innocent civilians, whole towns and cities in Syria AND around the globe. The Putin government are clearly terrorising the unprotected and defensless.
Lately putin has authorised bashar to use illegal weapons to set HUNDEDS of children on fire and whatch them burn!!!!!
Imagine a pro photographer clicking away while that happens!! What a hero he/she would be if they were able to tell the world through their images what Putin and his cousin in terror bashar are doing away from the eyes of the masses....

Turkey has seen MILLIONS literally, of widows children and innocent people cross the boarder begging for anything but to be sent back to Syria, certain torture and death.

Where are the pro photographers in Syria giving TRUE context to this assassination?! Where are the real brave pro's??

This photographer isn't brave at all? He is just purely lucky, f8 & be there. He was at the right place at the right time to sell this image for the right price. Oh, and he gets to make a better name for himself. Something I would have done too, I'm not telling him how he should do his job. Good shooting I say.

The photographer I mean.....

Hospitals were bombed from the air. The rebels do not have planes.

Link | Posted on Dec 22, 2016 at 17:29 UTC

It is obvious that the shooter needed a podium to make a statement. The photographer was part of that podium, and was probably never considered a target. The photographs registered the event. The video however also contains the message the shooter wanted to come across.

Subsequently, the media focused on the event, while the Turks and Russians convene to fight "terrorism", trying to detract focus from their own atrocities. A photo gets you only that far into the real issues.

Link | Posted on Dec 21, 2016 at 00:47 UTC as 129th comment
On article Have your say: Best prime lens of 2016 (152 comments in total)

Why are so many lenses missing from the list?

Link | Posted on Dec 9, 2016 at 13:09 UTC as 54th comment
In reply to:

lacix: Damn! I just bought the FE 50mm F1.8

also for €3000?

Link | Posted on Dec 7, 2016 at 19:39 UTC
On article Venus Laowa 12mm F2.8 Zero-D sample gallery (125 comments in total)
In reply to:

keepreal: The price for this Venus Laowa 12mm F2.8 lens is pretty steep. A similar lens which has both both auto focus and aperture linkage also would be, even with as good optical quality, except perhaps from one of the prime lens manufacturers - no pun intended.

I am beginning to wonder if the growing number of manufacturers whose lenses lack auto focus and aperture linkage to the camera body is because they do not know how to do the electronics. Samyang, as far as I am aware do provide AE on Canon but only for one of their lenses. But at least their lenses are often cheap in spite of good optics, which may be the reason.

The nearest competitor will be the new Samyang XP 14mm F2.4 for the same price, whose samples I have seen look a lot nicer at 100%.

Link | Posted on Nov 30, 2016 at 23:32 UTC
On article Venus Laowa 12mm F2.8 Zero-D sample gallery (125 comments in total)
In reply to:

keepreal: The price for this Venus Laowa 12mm F2.8 lens is pretty steep. A similar lens which has both both auto focus and aperture linkage also would be, even with as good optical quality, except perhaps from one of the prime lens manufacturers - no pun intended.

I am beginning to wonder if the growing number of manufacturers whose lenses lack auto focus and aperture linkage to the camera body is because they do not know how to do the electronics. Samyang, as far as I am aware do provide AE on Canon but only for one of their lenses. But at least their lenses are often cheap in spite of good optics, which may be the reason.

For less than this price you can buy a Tokina 16-28mm F2.8 including autofocus. Such lens is a lot more complex mechanically, electrically and in amount of glass. There is no reason this Laowa should be that expensive, the more so because the image quality seems barely okay below f/11.

Link | Posted on Nov 30, 2016 at 23:29 UTC
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