Is ND400 insufficient for some sun moments?

Question

I've taken a shot of the sun using my Tamron 70-300 (at 300) on my Nikon D5000 at 1/4000 and F40 and had attached the ND400 filter.

The shot was taken mostly to test the filter so I ignored the dirty window through which I shot.

However I was surprised to find out that even with all the controls turned to minimum luminosity and having the filter installed the sun was too bright. Maybe the time of day (local time around 09:00 AM, today, November 29th) was inappropriate for taking such pictures?

Or maybe the filter is not enough?

enter image description here

Make sure your ISO is turned down to its native ISO (usually as low as it can go, though some cameras have expanded ISOs on the low side). — Evan Krall, Nov 29 '11 at 07:44
Also make sure your sensor is clean -- you wouldn't want any sensor dust pretending to be a sun spot. — Evan Krall, Nov 29 '11 at 07:45
@all : I was considering stacking two ND400 filters. Would this be overkill? — Andrei Rînea, Nov 29 '11 at 18:21
Two ND filters would probably decrease contrast via flare, etc. However, you could open up your aperture in response, which could increase sharpness by decreasing refraction. — Evan Krall, Dec 01 '11 at 07:15

score 6 · Accepted Answer · answered Nov 29 '11 at 07:37

6

The pixels are not overexposed in any channel, and applying a heavy curve will reveal the darker edges and some dark spots. What you have is an exposed-to-the-right image of how the sun looks like - it is a big shiny ball. IMHO you should have enough data in RAW to tweak this into a usable image.

image in question with adjusted curve

answered Nov 29 '11 at 07:37

Imre

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I do have the RAW file (12bit, compressed, that's how D5000 does it :(( ) but the crop is real pixels. At 300mm 500px width is all I could get. I am seriously considering at least a teleconverter if I can't afford a 500mm or more .. – Andrei Rînea Nov 29 '11 at 16:06
@Andrei a 500mm would give you 750px, and a 2x TC with your current 300mm 1000px. To fill the frame height, you'd need about 1700mm, e.g. Sigma 300-800 with 2xTC. – Imre Nov 29 '11 at 20:16
so... obviously out of my budget. – Andrei Rînea Nov 30 '11 at 11:14
@AndreiRinea Since you're using a small aperture (and taking in the diffraction) anyway, there might be cheaper DIY options to explore. For example, a pinhole at the end of a 1700mm DIY tube plus the ND400. Or a 1000mm f/33 lens element (sorry, I couldn't find longer focal lengths in a quick search) at the end of a ~960mm tube (design the device so it allows you to move the glass back and forth for focusing), plus the ND400. – Imre Mar 06 '13 at 07:08
To stop the glass down further than f/33, you could make cardboard aperture discs (a la Lensbaby). – Imre Mar 06 '13 at 07:09

Is ND400 insufficient for some sun moments?

1 Answers1