Reverse lens adaptor

milos

Got a reverse lens adaptor cheap from E-Bay and am trying to fit it to my camera and reversed lens.
I have removed the Nikon 18 -55mm then put the adaptor ring on and then attached the 18-55mm front to the adaptor ring.
Switched everything on my D90 and the lens to manual and guess what i can see. Nothing Just Black

Any ideas

zerohamster

Is the aperature closed? try changing zoom (be carefull as this is not as simple as it sounds and you could cause damage to the focus ring as it is bearing all the force).
Try looking at something a centimeter away and see is it in focus.

have you tried looking at a light source to see if any light at all travels through the lens?

milos

Looked straight into my room light and am getting very little light. Tried to manuel focus but no luck. I cannot see anything at a centimeter unless I have a very strong light on it. i.e. a maglight

DaireQuinlan

Thats a G lens, right ? Your problem is that once taken off the camera they stop down the aperture all the way, so you're trying to shoot at F/22 or whatever.

You -can- get around this though, on the mount there's a little spring mounted lever, sliding this in the opposite directio will open up the aperture, so if you can find some way of jamming it open to whatever aperture you want you'll be all set.

It's one of the drawbacks of trying to use these G lenses for macro work. You also won't be able to meter with your D90 with a lens mounted like this (unless your reversal adapter is chipped) but I guess you're probably aware of that.

zerohamster

Yeah that does sound like the aperture is just stopped down. be careful what you jam the lever with as you dont want to damage it in doing so.
Also Im not sure about Nikon but try aperture priority mode and it should meter correctly (this is true for Canon models).

DaireQuinlan

zerohamster wrote: »

Also Im not sure about Nikon but try aperture priority mode and it should meter correctly (this is true for Canon models).

Nikon intentionally disabled metering on their consumer level bodies if you don't have a specific type of lens fitted, AI-P or AF and up. this was ostensibly to avoid confusion using older lenses (because the consumer bodies have no wayyy of telling what aperture is set on the lenses) but in actuality was probably done to diffrentiate the models a bit more features wise.
The upshot of this anyway is that while you can mount older lenses, or adapters, or bellows or whatever, metering doesn't work. Its a bit of a PITA.

zerohamster

DaireQuinlan wrote: »

Nikon intentionally disabled metering on their consumer level bodies if you don't have a specific type of lens fitted, AI-P or AF and up. this was ostensibly to avoid confusion using older lenses (because the consumer bodies have no wayyy of telling what aperture is set on the lenses) but in actuality was probably done to diffrentiate the models a bit more features wise.
The upshot of this anyway is that while you can mount older lenses, or adapters, or bellows or whatever, metering doesn't work. Its a bit of a PITA.

Ah I see, Thanks for that bit of info. I had no idea they would differentiate the models so much. I havent come across it so far on the bodies I have but it makes sense the way they are built to detect the aperture value.

milos

Great help all. It is an apeture problem and I am in the process of working that out. Hope the end result is worth it.

Got the ap sorted but the shots I am getting are only sharp in the centre. Here are some samples. can anyone help


_DSC2813 by milos5, on Flickr


_DSC2808 by milos5, on Flickr

zerohamster

When taking a macro shot youll probably want a wider DOF so try shooting with the aperture stopped down with whatever method you used to keep it fully open. because the lens is taking the photo so close it would be natural to lose detail at the edges but it depends on the lens I guess.
stopping the aperture down should help with sharpness and give you a wider DOF.

I hope that helps:).

EDIT: The lack of sharpness on the rest of the photo you mentioned seems to just be caused by the shallow depth of field at the angle you are shooting at.
Try taking a photo of text from directly top down and post the results so we can see if its the shallow DOF. The closer you are, the shallower the depth of field will be and if shot at an angle then you will only have a really shallow area of focus with a wide open aperture.

milos

Was able to rig up a cardboard selector for the apeture and I took this at about F18 (rough guess )
Am I on the right track


clematis heart by milos5, on Flickr

zerohamster

Yep looks like you got it sorted,there is a much greater depth of field. nice picture by the way.
Good luck with all the macro shots