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First light DMK41

JB80

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JB80

JB80

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Hi all,

Today I got to have my first play with the DMK on the PST briefly and it was a challenge to say the least, my kids picked the only day with a bit of sun to not have any naps so I had to abort for my own sanity.

Still I managed a couple of avis and thought I would ask a few questions as I'm not sure on a couple things.

I've attached a screen grab of what I was getting and would like to know if I'm on the right path with settings and the like as what I was using doesn't really seem the same as other peoples setting I have read.

I had gain down at 260 and gamma around 102 and brightness 0 but the exposure was 1/909 and that is what I was concerned about as I have seen much lower numbers stated.

It was also at 7.5fps as 15 wont work on the laptop, it will the PC though.

I guess the other thing is the sweet spot isn't terribly good as only part of the disc has detail. Is this normal or would a shorter exposure help?

All in all though I learned a few things today and am quite happy with the set up running on the Polarie and didn't have any focus issues beyond having trouble seeing the screen and fine tuning. Next time though....

Firstly no kids, it's too hard to concentrate.

I need to build another shade box.

And I think I should mount the polarie on the EQ2 as it'll just be easier when using this set up.

post-8383-0-71655900-1340892188_thumb.pn

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Photosbykev

Photosbykev

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You need some work on the focus to really nail it and drop the exposure a touch to darken the 'sweet spot'. There is a hint of a prominence which will be more visible by increasing the exposure or increasing the gamma (this reduces the contrast and allows more of a compromise bewtween surface detail and proms) Reducing the gamma, down to around 40-50, will dramatically increase the contrast which may help you with the focusing

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JB80

JB80

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Thanks Kev, I had the gamma at 40ish the other day but it was too cloudy to get anything out of, not sure why I changed it to be honest but I will give it a try.

I know the focussing needs work I was just happy that I could get it with plenty of give either side but I need to make up another shade box and the focus knob on the PST was hitting the handles on the tripod so I had to use the original focus knob which is more tricky and why I will use a different tripod next time.

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Photosbykev

Photosbykev

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Not an unreasonable value for the surface to see the prominence you will need a much longer exposure which will normally blow out the surface detail. By increasing the gamma value you should be able to find a compromise exposure to give the proms and surface but It is a compromise and not ideal for the best images

Sent from my iPhone using Tapatalk. Blame Apple for the typos and me for the content

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JB80

JB80

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Yeah I played around a bit with longer exposures, to be honest I plan on just taking two different at different exposures avis and combining them afterwards.

Hopefully I can sort the focus out as it was a nightmare with the canon, can a monitor be out of focus? How would I check?

I might be jumping the gun there hopefully.

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Photosbykev

Photosbykev

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The monitor will be accurate :) Depending on what software you are using it should be possible to digitally zoom the image on the monitor to help focusing. It is probably the most critical part of the process and I can spend 5-10 minutes focusing and tuning my system before I'm happy.

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JB80

JB80

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Right here is a screen grab from one of todays avi's, I dropped the exposure to 1/1250 and I'm not sure it could probably go down more.

Also focusing is going to be a pig as I spent more time on it and tried the gamma lower and zooming in which seems like it helps but well it doesn't seem any better in the end result, maybe a single frame would be better than a screen grab though.

Also need to play with the etalon but I want to sort everything out first.

I also have an avi with that bright flare(?) starting up which I thought was cool, I'll put it on youtube shortly. Was the M1 today associated with 1513?

But basically as usual focus seems to be my issue.

post-8383-0-41973900-1341075118_thumb.pn

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Photosbykev

Photosbykev

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Don't be too hard on yourself with the focus based on a screen grab or single frame. Get the best focus you can and then capture 60 seconds of video and process it thro Registax and then wavelets to get the best image

There is a world of difference between the on screen view and finished processed image

Sent from my iPhone using Tapatalk. Blame Apple for the typos and me for the content

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JB80

JB80

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That's true I guess, I need more patience I think. I was getting frustrated as I was battling clouds at the same time but I'm starting to get the feel for it all now. I'm going to try and process one of the avi's tonight and see what happens.

I still can't get the camera to shoot 15fps though.

Is that bright region a flare or something else? It ties right in for time with the M1 that happened today, when youtube is finished uploading I'll post it.

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Photosbykev

Photosbykev

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I don't have the signal on my phone to load a video but certainly process the video and apply wavelets to get the best out of the data. If you are using USB 2 ports on your computer there should be no reason why you can't achieve 15fps

Sent from my iPhone using Tapatalk. Blame Apple for the typos and me for the content

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JB80

JB80

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I will do that then with the second avi it's shorter but had no drift, I should get some time to do that tonight.

I assume they are usb 2.0 ports but really don't know, I'll check that too.

Here is the video I posted a thread with it in.

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