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Atik 460Ex or 383L?


gnomus

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I also find sky flats a bit hit and miss and don't bother. It might be the hugely variable light at twilight and dawn, with streetlights from towns and the ever present varying cloud cover.

I now simply point my scope at my oversized computer monitor during the day when it is back indoors with the ubiquitous notepad application maximized and this works fine for me. If it is too bright, I would simply put a whit t-shirt over it, but my 414ex doesn't seem to mind doing really short exposures. I don't actually do it very often, as everything remains attached to the scope, so the flats work for months.

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Naturally, this is all done just prior to imaging so the sky is absolutely clear.

/per

I have had issues getting Flats before the the Lights. I had a fairly large mote appear dead center on my Caldwell 19 run midway through the night. I had taken flats earlier as I waited for the forecasted clearing skies. I salvaged the image with clone, but you know that spot is always in my mind when I look at that image. I decided then I would always try to get Flats at the end of the run.

I did try sky flats when I captured my M101 as my DIY EL panel was suffering from bad electrical connections. I let APT automatically determine exposure for the filters used that night. Unfortunately the sky was brightening so quickly the flats were getting brighter as the sets progressed. I decided to fix my cheapo EL panel.

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  • 1 month later...

Sorry 4 intruding into the Flat file Issue :) I do have a  question regarding the sequencing in Artemis Capture.

Is there a way a to programm Artemis sequencer in an Individual sequence mod, apart from all the channels at the same repeat counts.

For instance I would like to do Ha 18 exposures @ 450 6oo s bin 1x1 and RGB 6 exposures @ 450 s bin 2x2.

How do i reduce the repeat count for a specified channel ?

In Main .S.Generator you can Indiviualy split the exposures. But Some negative driver  issues might pop up, if APT,MSG,Nebulosity, and Artemis are running on same Lap top.

Under a dark starry night unexpcted system crash and N-Files appear instead of Fits. Any suggestions to get out of this misery ?

CS

Rush

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My honest opinion? The ATIK 460EX. I had an ATIK 383L+ before my current QSI 660 (same sensor as the ATIK 460EX). Yes, the Kodak KAF-8300 sensor had nice FOV but it was noisy as hell. Using the Sony ICX694 sensor is a pleasure. No need for any darks whatsoever and the pixel size and image size give better resolution of the night sky. Mosaics may be needed for huge areas of sky (depending on telescope) but that's the same for any system, depending on your target.

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I suppose it depends on the type of imaging you do, if wide field stuff is your favourite pastime then you'll be looking for the biggest sensor you can get - 8300 or larger. It must be said though that there are many more small to medium sized targets than there are large ones and I have yet to run out of targets for the 490EX used in combination with the NP127is. I recognise this sensor's limitations though and I'm not at all frightened off Kodak sensors by some additional noise, which is why I went for a Kodak 16803 sensor for wide field work. What is frightening is the price of suitable 50x50mm good quality filters for the 16803 (almost equal in price to the camera). I will not be parting with the 490EX though any time soon, the extra sensitivty is worthwhile to me because the number of hours with a clear sky here in the UK are limited, and what I can capture with the Sony sensor would take perhaps twice as long with an 8300 sensor.

ChrisH

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For instance I would like to do Ha 18 exposures @ 450 6oo s bin 1x1 and RGB 6 exposures @ 450 s bin 2x2.

How do i reduce the repeat count for a specified channel ?

The only way I know around this is to put the Ha into the sequencer 3 times and the RGB only the once.  There are enough rows to allow for this.

Carole 

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Loving all these references to Sara's "knickers", ha ha.

Regarding sky flats, I always used to do sky flats with my DSLR, but I have found since I changed to a CCD camera and have a filter wheel on I get a light leak if I do flats or even darks in the daytime.  

I thought this was due to having a manual filterwheel as this has obviously holes to turn the wheel etc.  But it still happens sometimes since I got my EFW, yet these are the same telescopes that I used for my DSLR.   

So I always have to do darks and flats in the dark.  

However even if you are successful with taking sky flats, I'd advise putting something like Sara's knickers T shirt (which incidentally I think is a great idea), or a sheet of typing paper over the aperture to prevent accidentally capturing stars in twilight.  

N.B. Knicker elastic probably comes more naturally to us women.  I was at camp once and found I didn't have the correct weight on my counterweight and I was at the end of the counterweight shaft.  With no other counterweight with me I rummaged around in my tool box and the weight of a set of pliers was ideal, but how to fix it on so it wouldn't move?  I just happened to have some knicker elastic in my tool box too (don't ask!).  Bingo, did the trick.

https://lh3.googleusercontent.com/Rwp_QOydEUmBKFaw-roFAXRv-S8teianF2nazOAqNSM=w640-h480-no

Carole

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If you can forget the reference to my knickers :D I do have an update on this in case someone comes back to a similar quandary at some stage.

I had a Sony ICX814 for a year (That's equivalent to the Atik 490, QSI690) - I always found it too constrictive and I ended up doing mosaics for many DSO's. I note that in my initial post on this thread I wished I'd gone for a Kodak KAF8300 sensor. Well thanks to circumstances beyond my control, I have now got a KAF8300 sensor in the guide of a QSI683.

I have to say that despite what I read on these forums (which incidentally stopped me from getting this sensor in the first place.......) the Kodak sensor is not long in the tooth and noisy. I have used the same calibration and stacking methods as with the Sony chip and there's no more noise on the Kodak. 

So I would say that if anyone is put off (as I was) because of perceived issues, certainly the QSI variant is well worth considering. Also, with the built in filter wheel it allows you to use 1.25" filters which I am doing at f3.9 with no issues. Flats deal with the slightest vignette.

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Hi Sara, just got the QSI683, haven't bought filters for it yet and was wondering which make / nm you were using ?

Inspired by your complete Veil Neb :)

For Narrowband work I use the 1.25" 3nm Astrodon filters - They're about £410 each now I think. :(

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Oh God. Fortunately all my telescopes are round. Eek, my computer screen is oblong. Does this matter??

:eek: lly

Lol! it might... I've taken a risk and not gone for Astrodon but for Chroma. Normally these would be similar in price to Astrodon but I got them at a substantial saving - there were no discounts available on Astrodons to be had. However, I can find little info on people using Chroma filters for astronomy, and even less for their 3nM offering. I was given to understand Chroma actually make/made filters for Astrodon at one point? Details are fuzzy, but if they don't work as advertised I'm stuffed. :-)

Chris

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I'm afraid that my lack of funds to change to 2" Astrodon 3nm filters totally affected my camera choice - Initially it made me think that I'd have to stick with the smaller Sony sensor forever. Thankfully all works OK, so it's saved me trying to smuggle more Astrodons under the radar. They fit so nicely into a handbag that they were never even seen :D When they eventually came to light, they look so insignificant that I said they were about £50 each and that was believed :D..................

........... I'm afraid that I am a very naughty girl  :evil4:

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Can someone confirm that I'll be OK with 1.25" filters rather than 31mm unmounted imaging at f/4.9 WO Star 71 using the QSI683 ?

Dave

I can't confirm it Dave as I don't use that scope, but I am using a Tak reduced at f3.9 and the slight vignette is taken out with flats.

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Can someone confirm that I'll be OK with 1.25" filters rather than 31mm unmounted imaging at f/4.9 WO Star 71 using the QSI683 ?

Dave

I think you will. You won't be imaging at this level of kit without shooting flats and I'm confident (but not certain because I can't be) that this will work. I use 2 inch mounted with my Atik 11000. Atik say this will vignette. I'm running at F5 and posting everything I shoot. I see no real issue. In Tom's half of the tandem we have 2 inch unmounted and these vignette sligtly less. Let's not get excited, they both work fine with flats.

Olly

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Don't apologise, Sarah.  I am extremely grateful for your expertise in this matter.  It is helping me a lot with my research.  I have had another look at the wheels and I see that I can get a 7 carousel wheel for the EFW 2 that will take 36 mm unmounted filters.  I have no idea how 'unmounted' works as yet, but I think the 36 mm filters would allow me to use the 383L (and of course could be used with the ZWO.  That would mean that I could have L, R, G, B, Ha, OIII, and SII all set up in the wheel.  

Given that the 383L offers a larger field of view, I wonder why the 383L is roughly £250 cheaper than the 460EX.

the 36mm unmounted filters are perfect for the 383L,

1.25" are a little small for it.

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the 36mm unmounted filters are perfect for the 383L,

1.25" are a little small for it.

I think the filters may be closer to the sensor on the QSI, Astrodon recommend 31mm unmounted but don't specify a scope focal length.

Dave

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I'm afraid that my lack of funds to change to 2" Astrodon 3nm filters totally affected my camera choice - Initially it made me think that I'd have to stick with the smaller Sony sensor forever. Thankfully all works OK, so it's saved me trying to smuggle more Astrodons under the radar. They fit so nicely into a handbag that they were never even seen :D When they eventually came to light, they look so insignificant that I said they were about £50 each and that was believed :D..................

........... I'm afraid that I am a very naughty girl  :evil4:

A girl after my own heart Sara, I usually knock a nought off the end when asked the price of astro stuff, ignorance is bliss  :grin:

Dave

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