As mentioned last night, undeveloped film has been stacking up so I developed two rolls yesterday which were HP5+ from Ilford with a native ISO rating of 400. I pushed it to ISO 800. By this I mean that I set the camera for ISO 800 and shot normally. When I developed I developed it with the ISO 800 time. This means more time spent in the development fluid.
Pushing and pulling film, defined as processing the film at a faster or slower rating than the manufacturer suggests, is a great tool for film photographers. When I go on vacation I typically take some rolls of HP5 rated at ISO 400 and HP4 rated at ISO 125. If I am shooting in strong light I will load the ISO 125 film but for most of my shooting I like ISO 400.
But there are times when there is far too little light for ISO 400 and a tripod is not an option. I can then choose to shoot my ISO 400 film at ISO 800 and let it sit in the development soup a little longer. The benefits are that I take less types of film with me while still being able to shoot a wide range of light conditions. Pushing and pulling film also gives it a different character to the shots.
The downsides are that the grain structure may increase beyond a point which is considered pleasing. The point at whcih this happens is very subjective however I find that high grain reminisent of Henry Cartier Bresson shots. Take a look at "The Decisive Moment" and you will see grain in all its glory.
The shot on the left (of the boat on a rack) was shot on HP5 and pushed to ISO 800. The shot on the right was also shot on HP5 but kept at ISO 400. Both developed on ID-11 at a 1:1 mixture.
A close up of both images shot the grain difference between the two. The pushed shot has larger grain size in the shadow regions. The amoung of grain does not change but the size does. Both have been scanned with a very poor scanner (it is fast and dirty but my real prints are made in the darkroom so I do not need high quality scans).
Below are the shots I took with my Nikon F2. The Lake District is a fantastic place with vibrant colors and wonderful people. After this roll I switched to some color film but I just ordered my C-41 chemicals to process those.
The shots of the hotel were meant (fell a bit short) to capture some of the old grandeur of the hotel. This place was popular in the 1930's and it was great to see its dated past in the decor.