Adam J

Its almost certainly caused by the L-eNhance filter, they are known for it. Its a feature not a defect as such. Adam

Cant possibly comment on that without knowing what they are asking for the 450D, but all in all the 6D is a better astronomy camera when modified than a 450D which is very old now. Adam

Yes, the point being that those giant slow professional scopes have massive sensors with massive pixels many many times the size of those used in hobby imaging. However, I have to note that your flux per pixel also increases if you use a reducer. The overall problem with the Myth is that it will not take account of the reality that you have many more combinations of aperture and focal length scopes available on the market than you have sensors with different dimensions and pixel sizes. So in reality you have a choice if you want to image faster, You can try to find a sensor with larger pixels and or FOV (£££), or you can bin 2x2 the image at native focal length and increase your signal to noise that way, but you are also reducing your images total pixel count or you can use a reducer and have the same or slightly better effect and also increase your FOV at the same time. Finally swapping out a reducer / flattener to suit different targets is preferable to paying out for two scopes or alternatively paying for two cameras with different pixel sizes. There are also optical advantages to using a reducer to achieve a target focal length at a given aperture as opposed to negatively with a faster F-ratio optic. Adam

So what are its deficiencies in your opinion as a RASA owner? I have been taking note of RASA images and my possibly controversial opinion is that they can seem to lack in terms of resolved detain in brighter targets. I guess the poor stellar performance is a more directly visible symptom of this. What I mean by that is that when I see RASA images of bright targets such as the North America Nebula (as one example), I tend to think that they appear soft in comparison to images by similar focal length refactors at or about F5. This is something that I would anticipate from examining the published spot diagrams for a RASA. But its probably also caused by the fact that RASA imaging leans towards OSC cameras for various reasons and so the softer optics are combined with the lower sampling of an OSC (most so in red) to limit the resolved detail. Now this is only the case for bright targets when both the F2 RASA and the F5 refactor can achieve a suitably high signal to noise ratio within a reasonable amount of time. When the RASA of course wins is when imaging time is very limited or when the target is very dim. As in these cases the signal to noise ratio of a slower system will be the limiting factor in terms of resolved detail or in the extreme case the very ability to detect the presence of the object at all. As a side note, I think this is a reasonably advanced topic to be found in the getting started with imaging section. Unless we are advocating a RASA or a Hyperbolic Newtonian a starter scope. Adam

In that case I really dont think that you will gain anything by switching.

I see that you will be using the 120 for guiding. Honestly these days I would recommend a ASI585mc as opposed to a DSLR with the nest step up being a cooled 533mc. I started out by astro modifying my own DSLR as I really did not have the budget for the CCD astronomy cameras of the time, i have even done a mono conversion and cooled it. But these days that balance has shifted so unless you have a sub £200 budget then a dedicated camera is the answer. Adam

Why do you end up cropping the 533, what scope are you using it with and what are you taking images of? But in almost all cases I would see that as a downgrade. Adam

just so long as they are not white when you cover the scope.

Just recomended that in a different thread: In short yes you are better off with FPL53 and sometimes by a significant margin. If you want to know what an average FPL51 equiverlent looks like at F6.5 then look at the Evolux 62 and the discussion in this thread. The long winded version is that the ED glass type is not everything and there are some excerlent FLP51 scopes out and about (though mostly triplets), but in the end on balance you are better off with premium glass or people would not be paying for it. But all this discussion about the importance of glass type in this instance is unimportant, the important thing is that you are thinking about the RVO Horizon 60ED and that it is a great choice in my opinion and a proven good performer across the verious copies from RVO or WO or TS or Altair Astro I have seen very very few complaints so go press the buy now button and dont overthink it. Dont underestimate the importance of that Zygo interferometre report either, as that kind of in house testing by RVO is going to mean that any really duff copies are going to be weeded out. I done belieive the other clones of the scope are offering that. Adam

People are expecting too much from a scope that is not using permium ED glass. This is the equiverlent: https://www.rothervalleyoptics.co.uk/rvo-horizon-60-ed-doublet-refractor-ota.html Or the TS, they are proven and much better corrected than the Evolux. the redcat and certainly the Samyang 135 are much shorter focal lengths. Adam

Yep and lots of people on the internet think that the world is flat. The trick is not being seduced into believing things just because they tell you what you want to hear. Adam

How do you know its on a EQ2 OP may have upgraded? Honestly, I think that you are vastly better off opting for something like a ASI585mc than a DSLR these days. Especially on a scope like the 130M as you will only have a 1.25 inch focuser anyway and that will not fully illuminate a APSC sized sensor like in the 4000D. More to the point you will not get a coma corrector for the 1.25inch focuser either and so again your wasting your time with a larger sensor. If you do have a EQ2 you are not going to be able to do DSO imaging in any serious way, but you can image the moon and planets and a ASI585mc would be an excerlent tool for that at about the same cost as a 4000D new. But the best part is that if you do change your mount and then later your scope you will have a camera that is capable of DSO imaging and or could be used as a guide camera in the future, so its a good investment. Honestly, with this camera now on the market its hard for me to recommend a DSLR for beginners unless their budget is sub £200 and even then it would assume they are willing to perform an astro modification themselves as if not then your still talking about paying more than a 585mc. Dont worry about people telling you what you cant do and focus on what you can do with the tools you have. https://www.firstlightoptics.com/zwo-cameras/zwo-asi-585mc-usb-3-camera.html Adam

Well, its more trouble that its worth for an 80ED but if your sure that you are going to eventually move to the C14 that makes sense. What I would says is how do you currently polar align? If its with the guide scope then you are not going to be able to do that with the avaliable FOV on a off axis guider. Adam

Makes me wonder if its not using the internal memory and only working on USB 2

Might have frozen together. Or the cable was out of specification or maybe the port had a fault. Probably fixable with a sildering iron, you just need a new port. Adam

Steve I think that wires have been crossed some place, I looked back through this thread and unless I have missed it there is no mention of an Esprit 100? I think you may be mixing up two different issues from two different forum members? Adam

and whats the Flat6A adjusted to? Edit seems you fixed it. Adam

What Ha you are getting with the R filter is actually HA + light polition, the light polution is much reduced with the Ha filter and so you get much higher signal to noise and scan stretch the specific Ha regions much harder then add them to the R channel. Adam

Its all subjective, some are bothered by things others are not, but in your linked images the scope is showing pinching in the flaming star nabula image at the very least. Also in the star test shots posted my pipnina there are signes of both pinching and decentering assuming the artifical star was centered on the sensor. Edit: Just seen you used a mobile phone, thats not ideal, you could be picking up aberations from the eyepeice for example. Normally I would just use a small pixel guide camera for a star test with no eyepeice involved looking at the defocused diffraction rings. Adam

Can I see your latest image so I can see what your looking at? Also if you have any star test (intra and extra focal) that would be useful. Can only really give an opinion after doing that. But what I would say is that the general rule is that if stars look ok in the centre of the image then its probably just needs some TLC. Adam

Ah, that is unfortunate, I thought that you had just purchased it. The trouble with this sort of thing is that often people only see issues with optics as their experience increases and so by the time they have the experience to see that there is a issue its out of warranty. There are people who will fix it for you at a cost. But most of those are in the EU so involve postage. Interested to hear how its resolved and I can give you some contacts if you FLO cant help. Adam

I have seen good and bad examples of both. What I will say is that I will take a colimatable lens cell over a none colimateble lens cell any day and the GT71 and GT81 are not colimatable. Adam

Good news, I am sure they will sort it for you. Adam

Peter, just want to politely note that although I am quite happy to give my opinion as a scientist, I don't want to be drawn into a debate with the supplier. Adam

You certainly dont need to retake your bias or your darks as these will not change with optics. You would be well advised to retake your flats though as any flight colimation error or tilt in your system (and nothing is perfect) will result in the illumination profile changing slightly with rotation. Adam