russellhq

I'm not sure the conclusion is too clear. The mono sensor appears to be more sensitive to red, but this is only because it's also receiving green and blue light. If you exposed the sensors to just red light, you would find the microlenses are still more sensitive.

I could try taking a flat with the SII filter. This would guarantee that only red photos are hitting the sensor and I could then make a direct comparison between the bayer matrix side and debayered side and not have to worry about double counting photons (as from the charts, it looks like the RGB filters overlap making it difficult to draw a comparison)

Here's a bigger chart, looks like a 50% gain to me.

Do you remember what grade the diamond paste was? I was considering trying a very fine grade (0.1um) diamond paste: https://www.cromwell.co.uk/ENG2571000A Or an extra fine (0.05um) alumina suspension: http://www.agarscientific.com/general-consumables/polishing-grinding-materials/polishing-aluminas.html This would be used to clean up the sensor after scraping to remove the remaining bits.

Thanks for the links, I especially like this image! Nice idea for keeping the camera sealed!

Gina, have you noticed a layer below the bayer matrix? When I've been debayering the 1100D, once I've gotten the green layer off with a scraper, there's a dull gold layer underneath. If I then use a polishing compound, the dull layer is removed and there's a second gold layer.

This is what I don't understand. How can the lens increase the performance by a factor of 3?

Here's one method : http://www.google.com/patents/US8530356 Plus side, the gold wires won't react with the nitric acid.

I was considering the possibility of debayering half the sensor for imaging galaxies. Half the sensor should be plenty big enough and you have a camera that will capture luminance and rgb just by shifting the scope slightly. No idea if it would work though!

I'm pretty sure the black level on the 1100D is 2046-2048, but this was already subtracted from the values I posted

I'm not sure it works this way. A good experiment would be to compare a mono ccd luminance Flat frame with mono ccd R, G & B filtered Flat Frame. And see if the ADUs add up?

Has anyone noticed that the 1100D signal levels seem to drop once debayered? I debayered half the sensor and took a flat then measured the pixel values on either side. The debayered side was on average lower. Here's an example of the data I recorded: Debayered Results Pixel 1: 1246 Pixel 2: 1265 Pixel 3: 1231 Pixel 4: 1292 Average: 1258 Original Results R: 786 G: 1442 G: 1444 B: 1491 Average: 1291 Here's a copy of the flat: https://www.dropbox.com/s/uyz9zm6v7v0aj1g/IMG_5489.CR2

I wonder if a similar system could be made with water? No need to use a pump if it could.

Hmmm. This calc gives a dew point of -11C which agrees with the sketch. http://www.daytonashrae.org/psychrometrics_si.html Also, looking at various charts, -11C looks to be much closer to the ball park than -25C I'm afraid.

This is the one I'm thinking of getting: http://uk.farnell.com/jsp/search/productdetail.jsp?sku=1639752 It's 2A at 15.7V. dT 75C The next one up is 3.9A at 15.7V. dT 75C: that might be too much power.

The tests from elenhinan also suggest there is little to be gained from going below 0°C. https://ragnablade.myon.no/?page_id=11&page=3

RH is higher because it's colder. But you should find that the absolute humidity is lower.

Yeah, you need to look up your psychrometric charts or get a calculator. I was thinking that the air in your freezer should have a lower water content to start with. Maybe worth filling your box with air from there

Looking good so far, might be an over night job though?

I wonder if you could make some kind of bladder or bellow that would allow you to control a lever from outside the box while keeping it sealed at the same time?

Double sided tape sounds like a good idea. And I'm interested to see the lever arrangement you come up with.

Maybe it would help to orientate the sensor in the vertical position and do 1 row at a time. That way, gravity will tend the epoxy to flow away from the sensor.

I've been thinking about option 1 myself. I was considering placing the sensor in a sealed metal tin (like a biscuit tin), filled with some desiccant and leave it over night to dry. Then put it in the oven to re-set the epoxy.

It could be a difference in thermal expansion of the materials. Maybe when cooling down, something's contracting at a different rate and causing something to come loose? Then when things warm up the connection becomes good again? Also, good luck with the glass removal. I'm sure it'll work for you, I've tried it on 2 sensors and it worked flawlessly both times. Just make sure the glass falls onto something soft so you can reuse it later on.

I think the bayer matrix on the QHY8L can be removed with a solvent. That would make things a lot easier!