alacant

Hi

Welcome.

Some great locations in and around El Albir, along with hundreds of clear nights😀

20 hours ago, shaztronomer said:

50mm and my star adventurer

Hi

How about a 135mm or 200mm lens to complement your 50mm? They'd be fine on the sa. Good ones to look out for are the old Takumars which will fit your M3 with a cheap adapter. If you're any good at online auction, they go for around €50.

Cheers and HTH 

On 19/05/2023 at 00:07, BrianK said:

Trying to connect to https://asl-app.org fails

Hi

Try:

https://als-app.org/

Cheers and HTH

On 17/05/2023 at 10:33, wookie1965 said:

upgrade the springs can someone point me in the right direction for some please. 

Hi

10" mirror? We'd recommend 6 off, 1.6mm wire; 3 replacements and a further 3 passive springs using the locking screws as retainers.
These guys are good; less than a week to Spain. Not sure where you are but if you're in a rush, ask for local shipping at the checkout.

Full list of all sizes, here.

Cheers and HTH
 

1 hour ago, great_bear said:

the springs are out of the equation

Hi

The idea is that with adequate springs, the locking of the cell becomes an unnecessary source of further misalignment. Remember that locking a cell does nothing to prevent lateral movement of -especially in the OP's case- heavy mirrors within the same.

Recommendation: six springs. Use the -loose- locking screws simply as retainers for the three extra springs.

Cheers

2 hours ago, wookie1965 said:

I need to change the springs

Hi

If you want the collimation to hold on any budget Dobsonian at all tube angles (not just the angle at which you collimated), you'll need to seal the primary mirror to prevent lateral movement and stiffen the tube, as well as fit better springs. 
It's easy to do. We outline the procedure at the url below.. On a Dobsonian, you may need a pair of tube rings with aluminium profile top and bottom. This is for a gso, but Chinese Newtonians are similar:

https://linuxcb.blogspot.com/2022/06/gso-tube-support_22.html

Note, on a 10" steel tube, you may also have to reinforce the tube where the focuser is mounted. @laser_jock99 has articles on this.

Cheers and HTH

Hi everyone

Not much else to have a go at under a full moon this time of year. 

There seems to be a faint ring appearing beyond the brighter centre. Had a quick look online and can't see any definitive evidence of this so not sure if this is actually there or whether it's a reflection. This was with a UHC. Maybe one of the other narrow filters would help decide. Or, I suppose the usual tonic of adding more frames. This was about 2 hours.

Thanks for looking and do post if you've had a go at this, especially if you recorded anything beyond the owl.

20 minutes ago, bomberbaz said:

long way out of focus for the 2nd flat

You must not change the focus -or anything else in the optical train- between taking light and flat frames.

Hi

To help us diagnose, maybe post -links to- a light frame and one each of whatever calibration frames you used, along with a description of whatever hardware has produced such, optical train detail in particular.

Cheers

14 hours ago, bomberbaz said:

opinions

Hi

Guessing: There may be cloud on one or more of the frames? Light entering the telescope? Condensation? Non-corresponding flat frames? Difficult to say without more detail, but easily fixed. If you corrected each frame before registering and stacking, even better.

I used Siril, but I think ASTAP may have something similar.

Cheers and HTH

6 hours ago, 2Jules said:

Veil, Heart Orion nebula, M31, M33

Hi

You already have a good choice for some of these. For the rest, perhaps one of these. It won't trouble the heq5 and you'd still have loadsa € left for a monochrome camera, filters and other stuff.

Cheers and HTH.

Hi

Lots of us use this. It's not bulky.

More here.

Cheers and HTH

20 hours ago, Sarek said:

other thngs I can do

Hi

Excellent shot. Just keep adding frames, but if you want to give it a go...

700d? Hands on over several years with the 18Mp sensors and this model in particular:

- iso 800
- No dark frames of any type
- No bias frames
- Dither around 5-10px between each frame
- Use a clipping algorithm during stacking: sigma 5-2 works well for us

Processing:

Simply subtract the offset (2048) from the flat and light frames.
But of course, try differing values and combinations for yourself and please post back if you find anything better.

Cheers and HTH

23 hours ago, francis8 said:

I tried flats and dark flats

Well done, and all the more so for using experimentation to find what works for you.

Offset 50:

I'm not sure whether the 533 adjusts values between 14 bit and 16 bit. It may depend upon which software you're using.

To find out, simply take a bias frame with offset 50 using whichever capture software you use. Open in Siril and:

right clik -> statistics

Look at the median value and enter that value for the offset when processing in Siril. That should obviate the need for having to take both dark and dark-flat frames.

Cheers and HTH

1 hour ago, Matt S said:

Skymax 127

Hi

I think you may have missed focus or the seeing was poor. Not sure how many clear nights you have where you are but at 1500mm you're going to be limited to the few which have excellent seeing.  A few ideas:

How about attaching your 678 to a camera lens instead? There are some good examples to be had for under €100 e.g. fixed focal length Takumar and Zeiss between 55mm and 200mm. Your mount will be able to cope admirably with that combination. Keep your 127 to look through and take -superb- photos of the surface of the moon.

Another idea is to fit a reducer.

Another, to upgrade the mount and guide but even then...

Cheers and HTH

22 hours ago, francis8 said:

don't have to take biases

Correct. To begin with, try without in-camera bias and without dark frames. The 533 is so clean anyway, you may find you're better without. Probably best of course, when you're familiar with the software, to try both with and without and decide for yourself.

22 hours ago, francis8 said:

offset was 50

So, enter =50 for the master bias.

Cheers 

19 hours ago, francis8 said:

the image contains many negative pixels

Hi

What offset did you use? I think 70 is the default. That should lose the negative values.

To keep it simple, take flat frames only and pre-process using a value of 70 for bias (enter =70 in  'Use bias') on the calibration tab.
Pre process then stack the flat frames with multiplicative normalisation to get a master flat.
Pre process the light frames using the same bias with the master flat
Register
Stack under additive normalisation and e.g. sigma-clip 5-2

If there's still noise (533 so I doubt it) then you can try adding dark frames.

Cheers and HTH

57 minutes ago, rickwayne said:

aren't they required for the math

In the real world, perhaps best to lose the theory. Hands on tells us to simply remove the offset.

57 minutes ago, rickwayne said:

darks/dark-flats don't work

For DSLRs, no. One of the main reasons is the impossibility of temperature matching.

Cheers and HTH

56 minutes ago, TerraC said:

So id be better off keeping at iso800

Yes.
 

56 minutes ago, TerraC said:

twice the number of exposures at say 30sec

No. Take as many exposures as your patience allows.  Use an exposure which  keeps the histogram centre or left thereof; the 18Mp sensor can take quite a bit of thrashing.
Pick a target away from the moon. 

Cheers and HTH

Hi

What do the logs say?

At that image scale you're likely going to need the larger maps.

Before you download, other stuff to try:
- make sure 'Use scale' is unchecked (it's under 'Options')
- up the settle time
- ensure focus is better than perfect
- make certain the mount is tracking
- bin 1
- a rich star field high in the sky
- unity gain (I think on a 678 it's 100) 
- a shorter exposure
- a longer exposure

If still no go, download

If it still doesn't work, go with ASTAP.

Cheers and HTH

4 minutes ago, TerraC said:

Iso on this one was 400

Hi

Keep the ISO at 800. 

600d, so take no dark frames of any sort. Simply calibrate the light and flat frames by subtracting the offset. The easiest way to do that is by using Siril, the added advantage of which is that it will also take care of any banding.

Cheers and HTH

15 hours ago, Mikey0368 said:

parking it normally

Hi

Maybe there is confusion between 'park' and 'home'? AFAIK, there are an infinite number of possible park positions but the home position is unique to your site. 

It sounds as if the motor is turning, but the worm is not meshing with the crown. I couldn't find any detail on worm adjustment as I don't think anyone has had a 350 to bits yet so maybe best to ask SW about the noise.

If you are now beginning sessions with 'autohome' and have set park relative to that, ignore what follows...

The only way our EQ8-r (same board, same encoders, same firmware) knows where it is, is by first registering the position of the axis encoders. This is most easily done by issuing the 'autohome' command. Under INDI eqmod, we can perform this without having to resort to the handbox. Under eqascom, you must first issue autohome from the hand controller. To have predictable parking and slewing, everything must be measured relative to the autohome position. Just in case, remove any plate solving coordinates you may have stored before you  begin.

Once you have the home position set correctly, simply slew to where you want to park and save that position via eqascom. 

Apart from that, am out of ideas but HTH anyway

1 hour ago, TerraC said:

i'll need to have a go at cleaning

Hi

No need to clean as no matter how hard you try, you'll never get rid of all the dust in the optical train. 
Unless the sensor is damaged, flat frames will correct the dark areas and tidy your image in other ways.

We don't know what DSLR you used so can only guess, but the blue banding could be a defective row of pixels on the sensor, you've left the memory card in the camera, electrical interference, a faulty cable, introduced by old camera firmware...  In any case, it's easily removed in processing.

Cheers and HTH

6 minutes ago, scotty38 said:

Do you need or want USB3

For taking video of a planet, it would be nice. Otherwise 5 minute frames of a galaxy present no problem over usb2.

Dunno. Still thinking...

4 hours ago, Budgie1 said:

Active USB 3 cable

OK and thanks for the reply.

I'm being particularly thick today so I can't find one.

It appears simple enough now I know what I'm looking for, but seems impossible to find.

A 3m active usb3 cable with these plugs at either end.

I've tried in English and Spanish... nada.

Any ideas?

TIA