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“Lens not attached” Nikon + RedCat 51

Sky-Watcher Star Adventurer William Optics Redcat 51 Equipment Help Needed Troubleshooting
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Astro avatar
Astro avatar
Hello all,
After finally getting off my but and buying some better equipment I am finally moving closer to targets. 
for the first time I finally set up all my new gear last night. 

WO Redcat 51
Nikon d5100
Star Adventurer 2i pro
Ioptron SS tripod

And after that first set up now I find myself here in order to get your help on figuring out what I screwed up. 
hehehe

so, when I attach the scope I cannot adjust my f stop.  I see “F—“ on my dslr menu. 
I tried a Nikkor 50mm lens and I can manually change my f stop but then Redcat back on and I’m back to “F—“

anyone else seen this?
Thoughts, suggestions?

thanks in advance for any help you can provide 
Jeremiah
andrea tasselli avatar
andrea tasselli avatar
Have you set the Mode Dial to M?
Thomas avatar
Thomas avatar
The Redcat is a set f/4.9, you won't be able to adjust the f-stop on that scope. You will have to change ISO and shutter speed to make any changes you want. And as mentioned, M-mode is the best to use.
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Astro avatar
Astro avatar
Andrea/Thomas,
thank you for your responses. 

I did indeed have the camera set to manual “M” mode (the second time, hehehe)

Thomas, maybe I’m not understanding correctly. I know the scope is a f4.9 but I should still be able to stop down in my dslr menu right?
either way, the OTA isn’t talking to the camera so I should have to set the dslr to 4.9 so that the camera body is matching the OTA?

sorry for my ignorance, I just haven’t found any articles explaining this and I’m trying to understand how to use an OTA with my dslr. 


update:
I just looked up some videos of people using a Redcat and after some careful pausing I got a view of a canon dslr menu that showed “F00” so it seems I really am worried about nothing? (I hope)

thanks again 
Jeremiah
andrea tasselli avatar
andrea tasselli avatar
Astro:
Andrea/Thomas,
thank you for your responses. 

I did indeed have the camera set to manual “M” mode (the second time, hehehe)

Thomas, maybe I’m not understanding correctly. I know the scope is a f4.9 but I should still be able to stop down in my dslr menu right?
either way, the OTA isn’t talking to the camera so I should have to set the dslr to 4.9 so that the camera body is matching the OTA?

sorry for my ignorance, I just haven’t found any articles explaining this and I’m trying to understand how to use an OTA with my dslr. 

thanks again 
Jeremiah

There is nothing you can do except set the exposure time and the ISO (use 200). From the point of view of a DSLR a telescope is just an entirely manual lens.
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Thomas avatar
Thomas avatar
Astro:
Andrea/Thomas,
thank you for your responses. 

I did indeed have the camera set to manual “M” mode (the second time, hehehe)

Thomas, maybe I’m not understanding correctly. I know the scope is a f4.9 but I should still be able to stop down in my dslr menu right?
either way, the OTA isn’t talking to the camera so I should have to set the dslr to 4.9 so that the camera body is matching the OTA?

sorry for my ignorance, I just haven’t found any articles explaining this and I’m trying to understand how to use an OTA with my dslr. 

thanks again 
Jeremiah

No, you don't have to match the f-stop in your camera, it will just appear blank. There are no electrical contacts for the camera to talk to the scope so it only sees it as a full manual lens. The stepping down is set in the camera but physically happens in the lens. In this case, since the scope is fixed, no adjustments can take place in terms of f-stop.
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Astro avatar
Astro avatar
I’ll try that Andrea. Thank you BOTH.
weather permitting I’m going to be in a bortle 3 next weekend so hopefully I can reply back via an Astro image soon. 

thanks all,
Jeremiah