Hi, I have a canon 450d with the standatd 18-55 mm lens ( C class ). I have a wide angle adapter lens screwed on the end.
I am finding that quite a few fotos are not 100% in focus if I zoom into the pic from the PC.
My question would be: Would it be in my best interest to buy a better quality lens such as a B class ? I am just wondering if the time taken for the auto focus is not fast enough and a better quality lens would be faster to focus on the subject ?
Thanks
Lance
ps) I have looked on the net and my lens does not have USM (ultrasonic motor) - I believe having a lens with this would help with auto focus ?
Thanks
I am not sure what your problem is. Are the images sharp, but just a bit soft: this is more or less normal for a basic lens like that. Maybe use a smaller aperture to increase sharpness.
Or are the imagesnot sharp at all : then it could be something like the lens not focussing at all, maybe due to dome port characteristics: there is a virtual image where the lens focusses on. If it is too close, the lens might not be able to focus. Dont know what you mean by the wide angle adapter.
Thanks for the feedback. I will definitely try the aperture. I normally shoot on 5.6 with 200 speed.
I probably am trying to get too close to the subject.
I have read that optical quality is reduced. Maybe I should do one dive without it on - and see.
Thanks for the info again - appreciate it.
Lance
I am not sure what your problem is. Are the images sharp, but just a bit soft: this is more or less normal for a basic lens like that. Maybe use a smaller aperture to increase sharpness.
Or are the imagesnot sharp at all : then it could be something like the lens not focussing at all, maybe due to dome port characteristics: there is a virtual image where the lens focusses on. If it is too close, the lens might not be able to focus. Dont know what you mean by the wide angle adapter.
I'm fairly sure that with the 450D you won't be able to take a shot at all if focus isn't achieved. If you are hearing that little beep after half depressing the shutter, the camera thinks it has found focus. What port are you using.
USM isn't very important, just quieter and a few milliseconds faster - more about marketing in my opinion.
You will get much crisper results from a lens without adapters. If you possibly can, get a dedicated wide angle lens. The Tokina 10-17 fish eye is a great lens - crisp, close focus and relatively economic. I also like the Tokina 11-16 rectilinear but it's not as fashionable on here.
Hi Balrog, thanks so much for your input. I will take the adapter off and give it a bash on Saturday . Will look at prices of the Tokina.
i have a housing made by a local marine shop - after using it for a while I know that I must go with a proper housing. I did make a mistake. I have put up a post asking if anyone is selling a housing for the 450d - so I'll wait and see.
thanks again
I'm fairly sure that with the 450D you won't be able to take a shot at all if focus isn't achieved. If you are hearing that little beep after half depressing the shutter, the camera thinks it has found focus. What port are you using.
USM isn't very important, just quieter and a few milliseconds faster - more about marketing in my opinion.
You will get much crisper results from a lens without adapters. If you possibly can, get a dedicated wide angle lens. The Tokina 10-17 fish eye is a great lens - crisp, close focus and relatively economic. I also like the Tokina 11-16 rectilinear but it's not as fashionable on here.
please get rid of the wide angle adapter - that will destroy the whole point of shooting DSLR glass. it will effectively reduce your 18-55mm to the quality of point & shoot glass. get yourself a proper wide lens, like a fisheye or a wide rectilinear and reevaluate. fisheye's are easiest to use and get sharp results UW.
Also the dome port configuration & positioning needs to be catered to each lens specifically, that's why manufacturers often have a port extension ring for each specific lens. If you're custom housing port isn't balanced with your lens (and with the wide adapter it probably won't be) you can lose image quality very quickly i bet. I can't profess to know the details of the whole process, but i do know they need to be aligned carefully.
cheers,
chris
Hi Chris
This is very informative and I see things in a different light. Thank you so much for posting this here. I was battling with the idea of forking out a lot of money for a proper housing, but I need to re-look this seriously.
I love stills and am quite passionate about it - a new lens will be the way forward too.
Thanks again
Lance
please get rid of the wide angle adapter - that will destroy the whole point of shooting DSLR glass. it will effectively reduce your 18-55mm to the quality of point & shoot glass. get yourself a proper wide lens, like a fisheye or a wide rectilinear and reevaluate. fisheye's are easiest to use and get sharp results UW.
Also the dome port configuration & positioning needs to be catered to each lens specifically, that's why manufacturers often have a port extension ring for each specific lens. If you're custom housing port isn't balanced with your lens (and with the wide adapter it probably won't be) you can lose image quality very quickly i bet. I can't profess to know the details of the whole process, but i do know they need to be aligned carefully.
cheers,
chris
Lance - guess my two-cents would be that a slightly better (and more expensive lens) would make it sharper. In the past I have tried to cut corners by buying a lower end lens. The picture quality wasn't an issue, but the focusing was. The cheaper lens that I have used in the past took longer to focus. And while a slightly longer focusing time might not seem like much, you have to think that if you are zoomed in (55mm), even slight fluctuations in depth - with breathing and the like - can impact the focus of the shot.
Just a thought based on my experience.
good luck!
Hi
Thanks very much for this. I thought it may be a lens issue, and was told not to use the adapter that I currently use. I have been looking around for a suitable lens and I may have found it. Thanks so much, 'cos now I can go ahead and get a lens without thinking that I would have made a mistake. Appreciate it.
cheers
Lance - guess my two-cents would be that a slightly better (and more expensive lens) would make it sharper. In the past I have tried to cut corners by buying a lower end lens. The picture quality wasn't an issue, but the focusing was. The cheaper lens that I have used in the past took longer to focus. And while a slightly longer focusing time might not seem like much, you have to think that if you are zoomed in (55mm), even slight fluctuations in depth - with breathing and the like - can impact the focus of the shot.
