LMC & SMC Test

[avandonk]

The exterior lens hood on the 300mm lens has really made a difference. It is the equivalent of very good baffling that a high quality telescope has and even high quality lenses lack. It increases contrast and signal to noise. The Sag Sco mosaic is proof of this. I have tried to get the colours 'correct' by using the same parameters to process the LMC and SMC data as I used for the Sag Sco mosaic.

I took a quick set of survey data of the LMC and SMC. Gradients were a problem as all of the data was not collected at or near the zenith. It does give an idea though what is possible.

LMC image 4MB

http://d1355990.i49.quadrahosting.com.au/2010_06/lmc_c.jpg

SMC image 5MB

http://d1355990.i49.quadrahosting.com.au/2010_06/smc_c.jpg


The dust is becoming quite visible in both images. I used 15s, 30s, 60s and 120s exposures. There is still enough head room in the sensor to go as far as 240s to get the really faint stuff.

I also made an image with both galaxies at the same scale.

All we need is clear skies.

Bert

[DavidU]

Fabulous result. I have found a super black velvet at spotlight (I mean BLACK) that I want to line my shrouds with.
The improvement in gradients with this is real bang for the buck. Do you have a pic of the set up now?

[multiweb]

+1 . I've been a converted proponent of flocking and shielding for a while now. Good quality flocking material + good shielding = increased contrast. Some people might still not agree but I reckon the proof is in the pudding. :thumbsup: Unless you live in a dark skies area in the middle of the desert. Lucky you! ;)

[jase]

Interesting analysis Bert. Effective control of localised stray light can go along way. It is however difficult to make a conclusive comparison given varying environmental conditions. As others have highlighted there is little that can be done about air particles, dust, vapour etc being illuminated by a city's landscape. You need to get out to a dark sky site!

Are you trying any methods to compensate for the yellow/green hues contributed by the light pollution? I know some simply drop the green channel using curves or the selective colour tool. The trick is isolating it from data - not as easy as it sounds. The reason I ask is that in both images, I would have expected the red HII regions to pop a little more. Not to the level of a dedicated mono cam, but be more pronounced for a DSLR. Just a suggestion.

[avandonk]

It is easy to get it 'right' for bright objects Jase. I will push the image when I get better data. I have never been a proponent of popping! It should stand by itself.

Bert