Astrozoid

Hi Stefan, Yes, I am very happy that the lens seems to be very well centered. I admit to being a pixel peeper, but I am very satisfied with the performance of this lens wide open considering its ...

Thanks Alen, Typo. Thanks for catching that.  Fixed. Jerry

The North America Nebula, Deneb, Sadr, the Butterfly Nebula, and the Northern Coalsack , made an interesting field for second light for the little beast, my name for the Sigma Art f/1.4 lens on the ...

Hi Bill, That sounds pretty good to me. Thanks! Jerry

Thanks, I have the Z6. Jerru

Interesting. Thanks! Jerry

Video newbie here. What is the difference between: 1920 x 1080 (Full HD, Slow Motion); 30p 4x, 25p 4x, 24p 5x and 1920 x 1080 (Full HD): 120p, 100p, 60p, 50p, 30p, 25p, 24p ? What's the difference ...

Alen, It is really crazy awesome that you can do this! Outstanding. These are the golden days of astrophotography, we are lucky to be alive. :-D Jerry

Roger, I will address your specific comments below, but lets step back for a minute, look at the big picture, and see what you are arguing. Lets use some common sense. Someone asked if nd grad ...

Hi Alen, I'm in suburban New Jersey just across the river from Philadelphia. My dark site is in the Pine Barrens. The next closest is Cherry Springs, but that's 6 hours. It has been a while since I ...

I knew you would question my methodology. And that's fine. But they do have exactly the same stretch. I was very careful about that, and about using the same total exposure to make the comparison ...

Hi Alen, We must be blood brothers. :-)  Where are you located? Our situations are almost identical... well except my drive is more like 75 minutes each way. But it's still much more efficient to ...

I have some "scientific" comparisons here where you can see that a light pollution filter helped with both a reflection nebula as well as a galaxy: http://www.astropix.com/html/i_astrop/cls_filter.html

Roger, I agree with you about ND filters. The conversation had drifted and I was trying to clear it up. Folks who use no filters with unmodified cameras make the trade off in their time because ...

Do you mean a filter that blocks 50 percent of a certain wavelength is "scaling or multiplying" it by .5? If that's what you mean, I get it now. Thanks for explaining that. Roger saying light ...

What, are you talking about a software filter? Or are you saying a normal camera filter, like a narrowband filter, is a multiply? I don't understand. Multiply?  That doesn't make sense. . . . . .

Update: I shot some darks and the hot pixels in them don't match any in the lights. Don't know what is going on with that. Jerry

Hi Chris, I think very highly of it. I was kind of shocked myself at how good the single frame was. Probably because this was an easy target, the brightest part of the Milky Way. If you look in the ...

I've been pondering the Z6 and hot pixels. The camera has hot pixel suppression baked in that you can't turn off, but when I open a raw NEF in NX-D, and click astro noise reduction on and off, I ...

Hi Mark, I'm really happy with it for the most part. I haven't seen any kind of banding, and I pushed it really hard. The histogram was between 1/3 and 1/2 over from the left, but it still held the ...