bilbo

7 hours ago, Look left said:

thanks for the advice. Then I would need a 2" tube lens fitting to go into the Crayford with an SCT screw thread so I could then fit a spacer to get the 105 mm focal length and screw camera to it taking into account the focal lens position?

 Would this still work? As the focus isn't great I as its about 5  mm too long, I thought it would still focus but as suggested the f ratio would  maybe 0.6 anyreason whyfocus should be out.

Yes thats correct.  As long as there's enough back focus on the C6 to compensate for the addition of the focuser. I have the 8" & 9.25" so can't give you a concrete answer. I don't know why they make the crayfords so big, you only need a few mm travel.

Whereabouts are you, I'm in NE also

cheers

Steve

PS Pic below is an Esatto motorised focuser (67mm length) on a C8 SCT.  but when used on th edge hd it becomes a fine tuner for the focal reducer, (which is your original setup) link to blog

https://www.primalucelab.com/astronomy/blog/esatto-focuser-for-schmidt-cassegrain-and-edgehd-esatto-come-focheggiatore-per-schmidt-cassegrain-e-edgehd/

18 hours ago, SimM said:

So, to use the example image from above, the sun is 4.2mm and the sensor is 4.9mm x 7mm. A blocking filter that is not close to the camera sensor and that is only 6mm seems a bit borderline e.g. won't it vignette the camera sensor if it isn't sufficiently close to the camera sensor and that's why they recommend a bigger version for imaging.

Hi Simon

Lots of good points, The layout is objective, collimating lens, etalon, refocusing lens. Blocking filter is on camera side of diagonal. Attached a cutaway. 

You have triggered an OOPs in my head though,  The blocking filter that came with this had an issue, (long story and long fix which I need to write up). While it was away I had two other B600's one slightly enlarged. The bug in my head now is did I use the slightly enlarged one while I checked out the rest of the scope.  The mono image posted was part of the blocking filter tests I submitted to lunt so I'm 100% confident that was the stock one. I also observed an absolute mega prom coming way, way off the sun during the break in lockdown, sadly no camera as I was at the caravan and didn't notice any cutting off to suggest vignetting, but I could have had the sun off center. Now I need to double check the obs against a cam.

Thanks a million, You've give me something to do.

Pic below is the lunt cutaway, but they've been tinkering about a lot swapping in cheaper components.

Steve

1 hour ago, Nigella Bryant said:

I have a Lunt 60 DS it's a fantastic scope but with a b1200. I believe imaging is more difficult with the b600 but fine for visual. Image taken with my setup using Zwo ASI 178mmm. False colour added in PS CS2

That's just a dealer spin to get you to fork out (a lot) more cash, Lunt are a little more honest, on this occasion they say "it'll give you a little more wiggle room"

I've used the scope on all sorts of mounts. As long as you have a reasonably decent one and take a little care to make sure you level the tripod, It should remain in the frame with little intervention.  I've had it stay put for hours on an evolution alt az mount to such an extent that I can actually "shrink" the sensor area down using the ROI.  In reality 10 sec's is enough to dump down 500 images.

Not really into imaging but I usually spend a little time with the camera when I start to get too hot. The sensor used on the mono pic was an e2v560, (Machine vision camera with gigabit interface).  This throws out around 100MBytes, (not bits) per second at full tilt, e2v570 is the same physical size but has smaller pixels giving a resolution of 1600 x 1200. Pretty happy with both. I then just throw the resulting tiffs or AVI at autostakkert or registax (no idea what i'm doing), just select the files and keep pressing nextor go or whatever. That's as far as I go.

have fun

Steve

PS, Nice image Nigella

Hi Magnus

They're all pretty much designed for full disc viewing and imaging, I had an LS35, Great little scope and now have the LS60. Both will do full disc. Just Make sure the blocking filter is the B600 (6mm).  You'll gain nothing from buying one with a larger filter aside from a being able to get more "black" on a larger sensor.

I use mine on an evolution mount, Align on the Sun, barely have to touch it.

Steve

Found a pic from last year on LS60, pretty blank sun, but its using the sensors full resolution. 1280 x 1024, 6.78mm x 5.4mmm.

The focuser should be first, attached directly to the scope.

The distance between the reducer and the camera needs to be constant.  In your current setup adjusting the crayford will alter the distance between the focal reducer and the camera. This will alter the focal ratio up or down eg could change from 0.63 to 0.6 or 0.66 you would then need to use the scopes focuser to compensate and a vicious circle begins.

Steve

Here's an old pic from a test i did year's ago with a 3.3 reducer, setup is the same for any.  Focuser / reducer / spacers / Camera

Try and power as much of your equipment as independently as possible, IE seperate batteries for mount, scope, camera's, laptop and Dew control. As most of the kit is linked together by USB serial ethernet etc.  One failure has the potential to take out everything when they are sharing the same power source.

Any inverters should be pure sine wave and from a reputable company. Victron or Sterling being among the best.

I have a couple of 7Ah power tanks, A tracer lithium battery pack & The Evo mount has its own internal battery. Charging everything can be a bit of chew, Just have the "Wall Worts" ready when your ready to call it a night, bring the batts in first to warm up a little while you dismantle the rest of the kit.

All the best

Steve

Central Star appears to be 55 Cygnus, Not Deneb as previously thought,  I just assumed it was Debeb due to the brightness and nothing else could be seen.

On 27/11/2020 at 18:13, John said:

Just another thing - the 26mm Panaview will be showing some astigmatism at F/5 in the outer half of the field of view - stars elongated a bit like seagulls. The Panoptic should not be showing this so will be more useful to detect field curvature as vlaiv says.

 

 

 

Seem to be bang on the button, Just a bit of a shock to my brain.

Had to check a starsense this eve, So I popped the 183c protec on the back of the esprit with the flattener about 1mm short from required distance. Took a couple of snapshots from sharpcap, (don't know what I'mm doing there either)

10 secs exposure on the stars with gain around 50%, Sky was terrible. I think the cental star is Denb, barely visible to the naked eye. Used the moon for an approximate focus.

I think all the stars look reasonable, nothing like my experience at the eyepiece.  Its a bit rough & ready but you guys may be able to read more from it

Thanks Vlaiv & John.  Just the sort of help I need, Out of my comfort zone here with this, but what you say explains a lot.

I only got a short spell at the eyepiece due to glorious weather. As soon as we get some clear sky I'll give it another go taking your suggestions into account.

Thanks a million.

Steve

5 hours ago, Sp@ce_d said:

Hmm now you mention it I can't remember ever actually looking through mine.. 🧐 

I take it you got it for imaging primarily?.. get a camera on it you'll love it.

Have you tried any 2" acc's directly on it, Mine is all over the place, tricky to get a grip unless its a perfectly uniform tube, ie no grooves or slopes.

Got a couple of Cam's, EOS 1100, 183C Pro Tec, Atik Infinity, and a collection of MV camera's, Just never had the time to use them. I thought I'd try the esprit to motivate me a little more. Problem is once I start looking, I just keep looking.

A double edge sword I think, On the one hand I should have kept the Megrez 72 on the other hand if its "orrible" to look through then that might be just enough for me to get those camera's out.

Cheers

Steve

Hi All

Can anybody who owns an Esprit 80 tell me how they find it for visual use. I'm not at all happy with mine. Elongated stars as you move away from the centre on 26mm Panaview and 19mm Panoptic, 7mm Naglers pretty good.

I did notice that after popping in for a cup of tea, when I came back out the initial view seemed sharp then deteriorated, leaving me wondering, Me or the scope. Had a Megrez 72 for a long time never really experienced anything "off" on that but never really scrutinised it as I've always been an SCT guy.

I know f5 on an unflattened frac is pushing things, but I just expected a little better.

cheers

Steve

PS Not had a chance to try a cam on it

There’s really no one scope that can do everything.

An 8’ Dobsonian is the best purchase you can make for looking at the night sky, Its super simple to use and you will learn so much more. Just pick out a constellation and tour around it. You should be able to pick one up for very little money in the US and if at a later date you have some extra cash for an equatorial mount. you can pop a set of rings on it and use it on the mount.

Throw in a reasonably good pair of binoculars, a stable tripod and you have the best of everything for next to nothing. The double setup will also let you share the views with family/friends

Have Fun

Steve

Looked at Venus in daylight a few times this year.  Had planned ahead for this. Should be able to see the moon, But Venus is probably impossible due to the minimal illumination. However that’s not going to stop us is it. 

EDIT misread illumination of Venus, Its nearly 8% so definitely on the cards for the entire event. Just the clouds to contend with.

Potentially dangerous and if you’re going to align on sun don’t forget to cover finder.

Steve

Attached view from NE England. Centred on Venus, Just before start.

Hi All

For those who enjoy watching or snapping the ISS, and have some clear skies, You can see it tonight (15th), 16th, 17th, 4 times on each night.

Have fun

Steve

There are no Rolls Royces or Porsches. You're observing a single very tight wavelength, so for the most part everything gets reduced to a Vauxhall Corsa performance. Just like a formula one race in the rain. its a great equalizer, I have some "cheap" WA ep's that look identical to the Lunt models, They all work great, The Baader zooms also seem to work well as should everything really,  Main differences will be in the coatings on the ep's which could reduce transmission at Ha wavelengths and dim the image.

Just play about, try everything you have, have fun in the sun

Steve

Hi Roger

First Unless you've bought a scope with straight through blocking filter, don't even think about using that flip mirror, you'll destroy your camera or eyes instantly,  You must use the blocking filter supplied if it is the standard diagonal type.

Not greatest time to go solar, As we're at solar minimum the surface of the sun is blank for the most part.  Proms spring up though and there have been some nice ones.

Check http://halpha.nso.edu/   This will show the sun in Ha from various scopes around the world updated every minute. Look for the images with the little green boxes in the corner. These show the time lapsed in minutes since they were taken and any proms, spot, etc will show up and let you know whether or not its worth setting up. Even a blank sun can be worth the effort as a focussing exercise.

Before you start playing with the camera, you need to learn how to use the scope visually to get the best out of it.  Use an eyepiece that gives a full disc, I like my meade 26 or 19 panoptic, Concentrate on the edge and bring into focus as sharp as you can. If your lucky and there are both proms and surface detail, (check website) adjusting the tuner will either bring the proms or surface detail into sharper focus. readjust the focus to sharpen further.  Play around with proms and surface adjusting focus and tuning as needed.  You'll soon get the hang of it,  One other thing worth noting is that solar scopes have "sweet spots" where feature show up better. Focusing on a prom, Use your hand control to move it around in the field of view,  you will find that it will fade away to nothing or sharpen and brighten.

Once you've got this part out of the way the camera should be pretty straight forward for you.

All the best

Steve

Thank Marv

That was my best mate Bullet, A beagle and half, Died last October 12th.

Had to get another dog to keep me from going nuts,  Another beagle, but female born to a welsh hunting pack, brought up in Liverpool by Polish people who had to return to Poland.  She's been a challenge but kept me going, wouldn't be without her now

All The best

Steve

PS Keep an eye out on the ISS passes  4th to 11/12th, Dragon and Progress are both going up. Should be visible

Hi All

Just popped my head out to watch the ISS, I knew a couple of re supply missions were due, so I wanted to see if I could see the supply craft trailing the station.

"Three fingers" behind sure enough a faint dot trailing the ISS.

The only thing is the mission launch seems to have been moved to the 4th, (Just checked) So the big Q, Am I nuts.

A thought has just occurred to me though and that is, Has a previously docked craft been released for return.

ISS is back in the Sky at 18:13pm ALT 10 deg in the West, Finishes  ALT 51 deg Due South at 18:16pm. Only a three minute window

Take a look.

Steve

Hi

They are a cow to photograph with Auto-Everything.

Anyway cheers, Had to flip my head around a little as the auto rotate keeps turning things right side up, but it's the confirmation I needed, Both ends wired the same

I can now plug in without worrying about smoke signals, If the rain ever stops.

Thanks a million & all the best

Steve

Hi Guys

I've  managed to mix up my cables and have two 6 pin to 6pin cables, One wired pin 1 to 1, 2 to 2............etc, other wired in reverse Pin 1 to 8, 2 to 7 etc.

Could anyone with a Starsense check their Camera to Mount cables and let me know which is correct, pretty certain its 1 to 1 but just need to make sure

I've attached a pic of the "Wrong One"

Thanks

Steve

Causing light pollution is now legally the same as causing noise pollution, you just don't hear of many prosecutions.

If the light is excessive, intrusive or otherwise annoying ask the council nicely to so something about it. If they then don't remind them that they may be breaking the law.

Steve

Had a couple of minutes spare this morning so took at another look at last weekends big prom to see if I could "bring it out" a little

No Idea what I'm doing, normally just take single frames to capture spots

Steve

It would be nice if did, but I think it will have blasted into oblivion by tomorrow.

It was real wow at the eyepiece, just fell in lucky. had to drag out everything to try and catch it,  dodge the clouds and then rush it all away to get ready for work.

Looking forward to getting back home and looking through the rest of the captures.

cheers

Steve

Had the scope out today for testing, and caught this. That's Big