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01-22-2019, 07:09 AM   #1
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Out of Focus - Blood Moon
Lens: Tamron Adaptall 60-300 Camera: K-3 Photo Location: Indiana ISO: 800 Shutter Speed: 2s Aperture: F8 

All,

I took photos of the eclipse the other night. The bright moon or partial were fine, but when it came to the blood moon, I had difficulties with focus. I suspect one of two issues:

1. An iced-over lens. However, the lens elements themselves seemed fine, even when I had ice on the outside of the lens.

2. With the 2x teleconverter I was using, I couldn't get wide enough to capture the moon and color without motion blur. I suspect this is more likely.

Attached is the best example I was able to capture, with some lightening and haze-reduction in LR. It was roughly 600mm, give or take (due to imprecise effect of "2x" teleconverter). Any thoughts as to the lack of focus? Or other critiques? I am generally good with the manual focus, and I took about 10 photos, some which seemed in focus, some either side of that, and some based solely on focus confirmation.

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01-22-2019, 07:47 AM - 1 Like   #2
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Was it on a tripod and did you have SR turned off?
01-22-2019, 08:43 AM   #3
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QuoteOriginally posted by photolady95 Quote
Was it on a tripod and did you have SR turned off?
It was on a tripod. I believe SR was turned off, but I don't recall at this point. Something to ensure is off for astro, generally, then? Or just moon? Thank you!
01-22-2019, 10:58 AM   #4
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QuoteOriginally posted by jawats Quote
It was on a tripod. I believe SR was turned off, but I don't recall at this point. Something to ensure is off for astro, generally, then? Or just moon? Thank you!
Anytime it's on a tripod, SR should be turned off, IMO. I've found it helps keep blur down. Course a 2x TC isn't the best for long lenses either because they give you less light. I've never shot the moon on a 2s timer. That maybe your problem too. Moon shots are usually the f11 rule, f11 @ISO100 or @ISO200 shutter 1/200s to 1/400s so I've heard and or read here on the forum. My photography professor says f8. at those ISOs and shutter speeds.

01-22-2019, 11:36 AM   #5
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QuoteOriginally posted by photolady95 Quote
Anytime it's on a tripod, SR should be turned off, IMO. I've found it helps keep blur down. Course a 2x TC isn't the best for long lenses either because they give you less light. I've never shot the moon on a 2s timer. That maybe your problem too. Moon shots are usually the f11 rule, f11 @ISO100 or @ISO200 shutter 1/200s to 1/400s so I've heard and or read here on the forum. My photography professor says f8. at those ISOs and shutter speeds.
Thank you - I'll def. have to confirm SR is off when on tripod. I found that anything below 2s wasn't producing an image at all, so I think a wider lens might be necessary (or a telescope...). Thanks again, photolady!
01-22-2019, 11:43 AM - 1 Like   #6
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I've shot moon at 300mm and gotten good results at the settings I gave you. Yes, they were cropped but still the moon was in focus after the crop. Cropping in photography is allowed.
01-22-2019, 01:00 PM   #7
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How did you manually focus? I find live view much easier for the moon or stars than the viewfinder.

Where you using a remote and mirror lock? (this will disable SR by default, newer cameras might have options to override though)

Have you tested this combo out in the daytime on far away subjects before?

2 seconds might be borderline at this magnification, but I'm not sure that's the sole problem here. A non-eclipsed moon so much brighter, you might try photographing the moon the next few nights, you could at least see what you and your equipment is capable of with the necessity of a long exposure removed from the equation.
01-22-2019, 01:08 PM   #8
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QuoteOriginally posted by BrianR Quote
How did you manually focus? I find live view much easier for the moon or stars than the viewfinder.

Where you using a remote and mirror lock? (this will disable SR by default, newer cameras might have options to override though)

Have you tested this combo out in the daytime on far away subjects before?

2 seconds might be borderline at this magnification, but I'm not sure that's the sole problem here. A non-eclipsed moon so much brighter, you might try photographing the moon the next few nights, you could at least see what you and your equipment is capable of with the necessity of a long exposure removed from the equation.
Brian,

It was freezing and my equipment was icing, but attached is a photo of the moon from last night, with the same equipment. I got about 15 shots between cloud banks. This is cropped and enhanced in Lightroom. It seems that I have the focus towards the back of the moon fine, and the front is either out, or there's not enough highlighted features to tell.

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01-22-2019, 01:14 PM   #9
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QuoteOriginally posted by BrianR Quote
How did you manually focus? I find live view much easier for the moon or stars than the viewfinder.

Where you using a remote and mirror lock? (this will disable SR by default, newer cameras might have options to override though)

Have you tested this combo out in the daytime on far away subjects before?

2 seconds might be borderline at this magnification, but I'm not sure that's the sole problem here. A non-eclipsed moon so much brighter, you might try photographing the moon the next few nights, you could at least see what you and your equipment is capable of with the necessity of a long exposure removed from the equation.
Also, Brian, here are a couple more, same equipment, on other nights:

One from earlier in the eclipse, and two from late Dec.
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01-22-2019, 05:27 PM - 2 Likes   #10
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Chances are that with the teleconverter, your exposures ran a bit too long and at the magnification you showed, moved significantly while the exposure was being taken. A teleconverter multiplies the f value of your lens by the same amount making the effective f-stop fairly high. Your camera would compensate by extending the shutter time. This is particularly bad during totality since the moon is only a fraction of the brightness it is without the eclipse.

The remedy is to use a higher ISO to get shutter speeds down, and if that isn't possible, a tracking drive to follow the moon's movement.
01-22-2019, 05:29 PM   #11
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I shot with my 300mm f4 with 2x converter on my K3 on tripod (900mm as 35mm equivalent) with manual focus and ISO 100. Had great sharp photos of the moon leading up to the eclipse using f8 & 1/180 or f11 & 1/160. Then as the full eclipse arrived, I went to ISO 200 and f8 or f5.6 with longer and longer shutter speed getting to 15sec. After reviewing, I saw I lost lost sharp images somewhere in there. The pre-shot focus was fine. After all was done I noticed I had failed to turn SR off. All the bad shots were where the longer shutter durations were blurred by the SR affect. I screwed up. Got nice color though. Got to remember to check SR when long shutter duration is used. Kick self here!!!

JB
01-22-2019, 07:09 PM   #12
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QuoteOriginally posted by Bob 256 Quote
Chances are that with the teleconverter, your exposures ran a bit too long and at the magnification you showed, moved significantly while the exposure was being taken. A teleconverter multiplies the f value of your lens by the same amount making the effective f-stop fairly high. Your camera would compensate by extending the shutter time. This is particularly bad during totality since the moon is only a fraction of the brightness it is without the eclipse.

The remedy is to use a higher ISO to get shutter speeds down, and if that isn't possible, a tracking drive to follow the moon's movement.
The higher ISO washed out from noise, alas. I took all of my photos on manual settings and experimented with near-totality and totality, without success. However, I did not have as much time as I wished, as I was (with only slight jesting) nearing freeze burns on my toes.

I did buy a tracking mount (iOptron), but it's been too cold or too cloudy to align it well as of late.

Thanks for the advice!

---------- Post added 01-22-19 at 07:12 PM ----------

QuoteOriginally posted by Take-5-JB Quote
I shot with my 300mm f4 with 2x converter on my K3 on tripod (900mm as 35mm equivalent) with manual focus and ISO 100. Had great sharp photos of the moon leading up to the eclipse using f8 & 1/180 or f11 & 1/160. Then as the full eclipse arrived, I went to ISO 200 and f8 or f5.6 with longer and longer shutter speed getting to 15sec. After reviewing, I saw I lost lost sharp images somewhere in there. The pre-shot focus was fine. After all was done I noticed I had failed to turn SR off. All the bad shots were where the longer shutter durations were blurred by the SR affect. I screwed up. Got nice color though. Got to remember to check SR when long shutter duration is used. Kick self here!!!

JB
I will bet you that this is precisely what happened. I had the same experience, and I will bet it was an SR issue. Gotta remember that. Thank you!
01-22-2019, 07:41 PM - 2 Likes   #13
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At 600mm, the 3.9 micron pixels of the K-3 sensor subtend about 6.5 microradians. The moon (and stars) move about 72 microradians per second. During a 2 second exposure time, the moon would move about 22 pixels.

If the blur is about 22 pixels wide, than that's culprit.
01-22-2019, 08:09 PM   #14
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QuoteOriginally posted by photoptimist Quote
At 600mm, the 3.9 micron pixels of the K-3 sensor subtend about 6.5 microradians. The moon (and stars) move about 72 microradians per second. During a 2 second exposure time, the moon would move about 22 pixels.

If the blur is about 22 pixels wide, than that's culprit.
Amazing knowledge. I got most of that, I think. I had a bit of trouble, though, after the 600mm, and before the "If the blur..."
01-22-2019, 08:35 PM - 1 Like   #15
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QuoteOriginally posted by jawats Quote
Amazing knowledge. I got most of that, I think. I had a bit of trouble, though, after the 600mm, and before the "If the blur..."
Your shutter speed was way too slow.

The moon is much faster across the sky than the stars (20 seconds would be fine for them).

Last edited by clackers; 01-22-2019 at 08:45 PM.
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